High Tunnel Crop and Market Period Diversity

High tunnel use is very popular and has been increasing in Ohio and many other states for decades. Growers are now asking new questions partly because high tunnel production is so popular and increasing and has been practiced for so long on some farms, creating new challenges and opportunities.

“How can I utilize my high tunnel(s) more effectively year-round or fall through spring?” is one very frequently asked question. Many agree that spring-fall tomato harvests can offer the greatest revenue or profit potential. However, others have shown or are learning that harvesting other crops from their high tunnel(s) during summer and/or fall through spring can also be lucrative and beneficial in other ways. Many examples of this have been shared in recent Extension and other programs in Ohio and neighboring states. Working with multiple crops across more of or the entire year requires being familiar with conditions affecting their growth, quality, and potential costs of production and market (profit) potential. Labor and other input costs and how one figures costs of production are obvious factors. For example, one grower-speaker at a recent conference recently described high tunnel space on their farm as “rented,” meaning that their costs of production include how much time is required for a crop to be market-ready. This approach (calculation) directs them and, possibly, others: a) to include lower-cost, quicker-cycling, high value crops in their systems, and b) to be selective when devoting space to high value crops demanding more space, time, and labor. For some, producing multiple crops, managing their investments in crops prone to boom-bust supply-price cycles, and accessing markets through most of or the entire is key to their business. They describe how the approach can limit risk and increase opportunity.

As described in our Feb-3 VegNet article, we seeded Mokum carrot, Red Russian kale, Oriole Swiss chard, Red Pac pac choi, and Music garlic in early Oct-2023 and have given them “minimal” care since that time. Our goal was to discover/demonstrate the potential yield and quality of these crops when grown and overwintered in this way, although the kale, Swiss chard, and pac choi were appropriate for some markets in December-January. This approach may interest growers unfamiliar with and/or currently lacking the ability to make large investments in fall through spring production-harvesting. Recent samples taken from the carrot seedings demonstrate that growth is accelerating and roots are likely to be market-ready soon. A large number of other edible and non-edible crops can be overwintered and/or harvested successfully fall-through spring in Ohio.

Please contact Matt Kleinhenz (330.263.3810; kleinhenz.1@osu.edu) for more information.

 

OSU Extension Bi-Weekly Fruit & Vegetable Report – October 17th, 2023

The OSU Extension Fruit & Vegetable Report is written/published collectively by OSU Extension staff across the state. 

Biological Soil Health

When it comes to supporting healthy soils, the physical and chemical aspects of soil quality are often highlighted. However, the importance of biological activity and diversity, and how it influences soil structure and chemical properties (pH, electrical conductivity, etc.), is becoming increasingly appreciated in modern farming. As we discover more about the different microbe-microbe and microbe-plant interactions unfolding in the soil habitat, we can create better farming practices that optimize crop health and soil quality.

Three areas of soil health: physical, chemical, and biological. Image courtesy of University of Massachusetts. 

The source of and final destination of all soil life is soil organic matter (SOM). SOM consists of biological material in the soil, derived from plants, fungi, animals, and other organisms, that are in various stages of decomposition. Certain forms of SOM break down quickly and provide nutrients for crop use, others are more stable (i.e. inaccessible to microbial decay) and contribute to aggregate stability and tilth. A SOM content of 5% in mineral soils is considered high; in muck soils, SOM can be as high as 80%. Conservation ag practices like reduced tillage and cover cropping are used to support high levels of SOM for improved nutrient cycling, soil structure, and cation exchange capacity. 

The food webs that produce SOM are characterized by an astonishing diversity of soil life made up of bacteria, fungi, archaea, nematodes, protozoa, and other microfauna, as well as the larger organisms like springtails and earthworms higher up the food chain. These organisms not only drive nutrient cycling through consuming and contributing to SOM, but can influence crop health through more specialized relationships. Plant-growth promoting rhizobacteria that interact with plant roots can boost crop productivity by producing hormones, fixing atmospheric N, solubilizing P for increased availability, and inducing plant resistance to pathogens. The growing biologicals industry (biopesticides, biofertilizers, and biostimulants) is based on the premise that certain organisms benefit crop health through either direct interactions or interactions with other soil life. 

Keeping in mind how soil biodiversity and activity affect soil health through the lens of SOM and interactions between organisms can help us make decisions that support crops by maintaining a thriving, balanced soil habitat.

Examples of soil organisms at different scales – Microfauna: Azospirillium soil bacteria (top), Mesofauna: tardigrade (middle), Macrofauna: earthworm (bottom). Photos courtesy of Science Source (top), National Geographic (middle), Dan Brekke – Flickr (bottom).

Crop Updates

Vegetables

Cucurbits

Plectosporium leaf blight is being detected. Continue to watch for aphids, cucumber beetles and squash bugs. Significant damage was detected within the last week in harvested pumpkins due to large populations of cucumber beetles. Aphids can still be found in green foliage, and may be spotted via large accumulations of honey dew beneath healthy foliage.

Cucumber beetles feeding on harvested pumpkins. Photo by Frank Becker, OSU Extension.

Cole Crops

Alternaria leaf spot is being observed in brassicas. This pathogen is supported by warm, wet conditions. Cultural practices for reducing alternaria pressure include increasing crop spacing for improved airflow, crop rotation, tilling under crop residue after harvest and controlling brassica weeds (shepherd’s purse, wild mustard, wild radish, yellow rocket, etc.)  to decrease disease inoculum. Treating seed with hot water prior to planting may also help  to decrease prevalence of this seed-borne pathogen. Consult the Midwest Vegetable Guide for fungicide options in Brassicas.

Tomatoes/Peppers

Hoop house tomatoes are nearing the end. Powdery mildew, bacterial diseases, aphids, and other pests are all being observed under plastic. Late blight and early blight are prevalent in remaining field tomatoes. 

Anthracnose is continuing to be an issue on peppers and tomatoes. Infested fruits rapidly decline in quality and are unmarketable. Lesions are typically observed as sunken, round lesions on the fruit. At times you may also be able to see the salmon colored spores within the lesion on the fruit. 

Anthracnose on peppers. Photo by Frank Becker, OSU Extension. 

Fruit

Many orchards are nearing completion of harvest and pest monitoring traps are being taken down for the season. As tree fruits are harvested and leaves begin to fall, it may be a good opportunity to take a closer look at your trees and scout the trunk and branches for presence or evidence of insect pests such as scale and borers. Scouting for these pests now can help you make adjustments to your integrated pest management program.

October Small Fruit Updates

Dr. Gary Gao, Professor and Small Fruit Specialist, CFAES South Centers. The Ohio State University

Update on Long Cane Raspberry Project:

We are only getting a few straggling raspberries from our long cane raspberry trial at OSU South Centers in Piketon during the week of October 6, 2023. There were only enough for Gary to snack on. Pictured in the first photo is Kweli®. As you can tell from the picture, fruit color is still looking quite nice. Kweli® is an everbearing variety that is capable of producing two crops inside a high tunnel and out in the open field. Follow this link for more information on the variety: https://www.abbreeding.nl/varieties/kweli/?lang=en

We are still fine-tuning the method of growing long cane Kweli®. We just wrapped up our 2021-2023 Specialty Crop Block Grant (SCBG) funded by Ohio Department of Agriculture (ODA). There is a lot more to learn about this highly innovative production method. Fortunately, we received another SCBG from ODA to do just that!

Kweli® fruits. Photo by Dr. Gary Gao, The Ohio State University.

Gary was able to find several Tulameen raspberries from our long cane raspberry trial plot. This is definitely too late for the Tulameen harvest since it is a summer-bearing variety which does not produce fruits on primocanes. It was still neat to check them out. Earlier in the season, we harvested a lot of beautiful Tulameen fruits. Some of our grower cooperators were able to sell them for $9 per pint in a Columbus farmer’s market. Raspberry bushes in a long cane production system can produce 22,000 lbs. per acre! Tulameen is well suited for long cane raspberry production and is well known for its large fruit size and excellent taste! Follow this link – https://www.researchgate.net/publication/292928034_’Tulameen’_red_raspberry – for more information on Tulameen variety.

Tulameen fruits picked in October from our long cane raspberry trial. Photo by Dr. Gary Gao, The Ohio State University.

Late Leaf Rust on Raspberries:

Gary noticed that some of the raspberry bushes in their raspberry trial had late leaf rust. Late leaf rust on raspberry is a fungal disease. Follow link – https://ohioline.osu.edu/factsheet/plpath-fru-17#:~:text=Late%20leaf%20rust%20is%20caused,rust%20fungus%20is%20not%20systemic. -for more information on symptoms and management of this disease. Do not confuse this disease with orange rust of brambles. Fortunately, red raspberries are resistant to orange rust.

Late leaf rust on raspberries. Photo by Dr. Gary Gao, The Ohio State University.

Fall is for Figs in Ohio!

Even though fall is typically for apples, mums, and pumpkins, it is also for figs – well hardy figs for that matter. Gary has been picking hardy figs from their fig planting at OSU South Centers in Piketon from early September to now. The figs will keep ripening until frost. A high tunnel will extend the harvest season.  Our figs were from another Ohio Specialty Crop Block Grant funded by ODA a few years ago. The varieties in our trial are Brown Turkey, Hardy Chicago, and Olympian. Brown Turkey and Chicago Hardy performed the best in our trial. Follow this link https://ohioline.osu.edu/factsheet/hyg-1439 for more information.

OSU hardy fig trial. Photo by Dr. Gary Gao, The Ohio State University.

Brown Turkey figs from the hardy fig trial at OSU South Centers in Piketon. Photo by Dr. Gary Gao, The Ohio State University.

Berry Production Workshops Presented by OSU Extension in Medina County

I will be going to Medina County on Friday, October 27 to give two talks, one on blueberries and one on raspberries. Ms. Ashley Kulhanek, the Ag. and Natural Resource Educator, is organizing the program. I will show gardeners and growers how to grow blueberries and raspberries. Please call OSU Extension in Medina County at 330-725-4911 for more information and to RSVP!

This is our last bi-weekly report for the 2023 season. Thank you for reading and please feel free to direct any feedback on the report series to Chris Galbraith at galbraith.108@osu.edu.

Upcoming Events

December 5 – 7, Grand Rapids, MI, Great Lakes Fruit, Vegetable, & Farm Market Expo 

January 15 – 16, Columbus, OH, 2024 Ohio Produce Network

February 15 – 17, Newark, OH, 2024 Ohio Ecological Food and Farm Association (OEFFA) Conference

 

OSU Extension Bi-Weekly Fruit & Vegetable Report – September 28th, 2023

The OSU Extension Fruit & Vegetable Report is written/published collectively by OSU Extension staff across the state. 

View a recording of the OSU Extension Bi-Weekly Fruit & Vegetable Report updates below:

Strip Tillage

Strip tillage is a form of conservation tillage that attempts to combine the benefits of no-till and conventional tillage by working only the area where the crop will be planted. Leaving residue cover over the majority of the field protects the soil against erosion and helps to build organic matter, improve aggregate stability, and boost other indicators of soil health. Working the soil in the strip zone warms the soil faster and prepares a better seedbed to support plant growth. 

Components of a strip till unit – A) lead coulter for slicing through residue, B) row cleaners for parting residue, C) shank for fracturing and lifting soil, D) berm-building coulters to shape tilled soil into strip, & E) rolling basket for creating level seedbed. Photo courtesy of Orthsman/Unverferth Manufacturing. 

 

Strip-till in sweet corn stubble. Photo by Chris Galbraith, OSU Extension.

While strip till targets the benefits that come with integrating the two systems, there are downsides to consider as well. These mostly involve issues with cover crop and/or residue interference with growing the crop. Vigorous cover crops need to be terminated in a timely fashion and crop development can still be delayed in strip-till if the season begins cold and wet. Pests like slugs and voles can also build-up with the increased residue cover. The cost of the equipment can also be a substantial investment which creates a barrier to entry for many growers.

Many vegetables can be grown in strip tillage systems, including cucurbits, sweet corn, snap beans, potatoes, cole crops, carrots, and more. Recent studies at Michigan State University have found a slight yield increase from strip till in vegetable crops, but many of the issues mentioned can impact this (climate, residue management, pest pressure). It is important to consider the factors that go into making strip till a successful venture in order to make the most of the equipment and the practice.

For additional info on strip till in vegetables, check out this website on strip tillage from the Cornell Small Farms Program. 

Wildlife Control in Fruits & Vegetables

This season has been severe in terms of wildlife damage in specialty crops. Animals like deer, groundhogs, voles, raccoons, and birds have caused major losses on some farms. Dr. Marne Titchnell, wildlife program director for OSU Extension, recently gave an in-depth presentation at Farm Science Review on different wildlife mitigation strategies for growers. The information and slides can be found on her blog through the link below:

Managing and Preventing Damage from Wildlife in Fruits & Vegetables

OSU Extension Center for Cooperatives

Opportunities abound for farms when it comes to teaming up to save money and improve effectiveness through joint purchasing, collaborative marketing, and other similar practices. These types of partnerships between farm businesses is captured by the cooperative or “co-op” model where growers access resources and savings by acting together and making decisions as a group in certain scenarios. The Center for Cooperatives at OSU specializes in these sorts of opportunities and can offer guidance to growers who are interested in leveraging the benefits of organizing for collaborative business purposes.

Find more information at the center’s website. Read more about the topic of collaborative marketing in this recent article on the Center of Cooperatives blog.

Crop updates

Vegetables

Cole Crops

Heavy cross striped cabbageworm and imported cabbageworm feeding is still being observed in some brassica plantings. Aphids have made a late season push in brussel sprouts, cabbage, cauliflower and broccoli plantings. Cabbage aphids are typically a grayish color, and are often found amongst a waxy, white secretion which covers their body. Reproduction rates of these aphids are highest in temperatures between 50-68F. Scout for these pests on the underside of younger leaves, between leaf layers and on flower buds or seed stalks. It is recommended to treat cabbage when you see 1-2% of plants infested with aphids. There are a number of products that can be used to treat aphids in cabbage including Movento, Sivanto, Assail, Exirel and Beleaf. Prioritize products that have reduced toxicity (e.g., Beleaf) which will conserve natural enemy communities. Refer to the Midwest Vegetable production guide for other options. 

Cabbage aphid infestation. Photo by Frank Becker, OSU Extension. 

Cucurbits

Cucurbits are seeing upticks in a variety of beetles in flowers and fruit. These include corn rootworm species. Spotted cucumber beetles are active. Aphids are also beginning to be found with some more frequency in the fall vine crops. Squash bugs are also active within the crop. Most cucurbits do not have blooms in fields, so pyrethroid and carbamate applications may be applied (e.g., Sevin, Pounce, Capture). Refer to the Midwest Vegetable production guide for other options.

The pumpkin crop has been strong in Ohio this season. Many growers in northwest Ohio were able to manage downy mildew with fungicides. Plectosporium blight has been causing some problems for growers where fungicide spray coverage may not have been as thorough as desired. Most fungicide spray programs being used are adequate to limit impacts from plectosporium blight. Spray penetration into the canopy and coverage across the field is as important as selecting the right product.

Plectosporium blight on pumpkin, identified by light colored lesions on fruit, handles, and vines.  Photos by Frank Becker, OSU Extension.

Fruiting Vegetables 

Late blight has been confirmed in several tomato fields in and around Wayne County. Bacterial diseases have also begun to start, and with cool mornings and heavy dews, it will become increasingly more difficult to manage. 

Several high tunnel producers have reported dealing with broad mites/cyclamen mites in their high tunnel peppers. The mites feed on the fruit while it is still developing and their feeding damage causes the peppers to become russested and misshapen. The leaves may also appear distorted, almost as if they were drifted with herbicides. Keep in mind that these mites are in a different group than two-spotted spider mites. Therefore, it’s important to select control options that are appropriate and effective on this species. Sanitation and crop rotation are also important cultural control measures that need to be taken when dealing with mites in high tunnels.  

Onions 

Although the growing season is behind us for onions, curing is still ongoing, and some growers have reported some challenges with curing. Make sure that you are providing the proper conditions for curing onions. Less than ideal conditions will result in frustrations and losses of product. Ideal conditions are warm, dry, well ventilated areas. Ideal temperature range is between 75-90F. The other factor that contributes to losses while curing is not curing the best graded onions. Curing is not an attempt to bring quality back, only preserve it. Grading hard for only the best onions to be cured will help reduce the chance that rots begin to develop. Take note of any disease or insect issues that you have observed this year and use these notes to help you next year. Onions that may have had heavy thrips loads, or untreated disease infection during the season are not going to hold up as well as desired during the curing process. 

Green onions are seeing thrips populations slow down. Typically, thrips populations will decrease as we enter into Autumn and see these species move onto weedy hosts. 

Fruit

Sanitation is an important component of an integrated disease management program. In small fruit and tree fruit alike, there are diseases that can over winter on infested fruit, foliage and branches. As the season winds down, it is still important to scout for diseases that may be present, identify the disease and have a plan of action to manage the disease. Finding and removing mummy fruit, which are dried and shriveled fruit that are typically full of fungal structures, will help to significantly reduce disease inoculum from the production area. Too, mowing and mulching or raking away the leaves from around the trees and bushes reduces the amount of viable inoculum that may be overwintering in foliage. Much progress can be made towards disease management with efforts made in the fall. Taking these steps, and committing to them long term, helps to break disease cycles and reduce the overall pathogen load over time. 

Fruit rots are being observed in apples, including white rot and bitter rot. Bitter rot is common in apples during warm, wet conditions. For more information, take a look at this OSU article on bitter rot in apple. Marsoninna blotch is also found on apples. 

The pawpaw crop in Ohio this season has been later and smaller than past years. Pawpaw is a niche crop that is gaining popularity with Ohio consumers and can be used as an ingredient in specialty craft beers, ice cream, and other value-added items. For more information on pawpaw production, check out this factsheet from Cornell University. Learn more about the pawpaw industry in Ohio by visiting the Ohio PawPaw Growers Association website.

Pawpaw fruit cluster. Photo by Clemson University. 

 

Upcoming Events

September 30, Albany, OH OEFFA CSA Veggie Farm Tour

December 5 – 7, Grand Rapids, MI, Great Lakes Fruit, Vegetable, & Farm Market Expo 

January 15 – 16, Columbus, OH, 2024 Ohio Produce Network

February 15 – 17, Newark, OH, 2024 Ohio Ecological Food and Farm Association (OEFFA) Conference

 

OSU Extension Bi-Weekly Fruit & Vegetable Report – September 15th, 2023

The OSU Extension Fruit & Vegetable Report is written/published collectively by OSU Extension staff across the state. 

View a recording of the OSU Extension Bi-Weekly Fruit & Vegetable Report updates below:

Farm Science Review 2023

The Farm Science Review (FSR) is one of the nation’s premier farm shows and one of OSU Extension’s largest, most far-reaching educational programs. The event will be held at the Molly Caren Agricultural Center near London, Ohio on September 19th – 21st. The OSU Extension Fruit & Vegetable Team will be hosting a tent all 3 days that will feature presentations from academic and industry speakers on a variety of topics, including nutrient management, entomophagy, integrated pest management, variety trial results, farm marketing, and more. The OSU Extension Fruits & Vegetables exhibit will be located near the gazebo near the Utzinger Garden (booth 385). We hope to see you there!

Check out the 2023 Farm Science Review Program for further information.

Speaker schedule for OSU Extension Fruits & Vegetables exhibit at FSR 2023. Note: There will also be a presentation by Dr. Marne Titchnell, Extension Wildlife Program Director for OSU,  on wildlife management in fruits & vegetables on Wednesday, September 20th from 1:30 – 2:00 PM.

Purple carrot-seed moth detection

The OSU Plant & Pest Diagnostic Clinic (PPDC) recently received an insect sample that was identified to be purple carrot-seed moth (Depressaria depressana), a known pest of crops in the Apiaceae family. This was the first report of purple carrot-seed moth found in Ohio, though it has been found in neighboring states. The insect feeds on the flower heads of crops like carrot, parsnip, dill, celery, parsley, and more, but it is yet unknown if it will be an economically important pest of these crops in Ohio. Check out the article from PPDC for more information.

Please report any suspected larvae/adults with pictures to entomology@osu.edu or ppdc@osu.edu.

Purple carrot seed moth larvae (top) and adult (bottom). Photo by Iowa State University Extension (top) and University of Wisconsin-Madison Department of Entomology (bottom). 

Crop updates

Vegetables

Cucurbits

Downy mildew continues to wreak havoc in cucurbit plantings this time of year. As a refresher, here is a factsheet from Michigan State University on downy mildew mitigation. Powdery mildew pressure is reported to be increasing in southern Ohio. Striped cucumber beetles populations are declining in central/northeast Ohio and transitioning more towards higher numbers of corn rootworm beetles. Western corn rootworm, a look-alike of striped cucumber beetle, also feeds on cucurbits and can impact yield if heavy populations are present. Check out this article from Iowa State University for information on identifying different rootworm beetle pests. 

Virus symptoms are being observed in some melon plantings. There are various aphid-vectored potyviruses that affect cucurbits and they can be hard to differentiate from one another, though control practices are similar for all of them. The big 4 for cucurbit crops are cucumber mosaic virus, papaya ring spot virus, watermelon mosaic virus, and zucchini yellow mosaic virus. Like many crop diseases, management practices are preventative and include using resistant varieties or planting earlier to ensure harvest before viral symptoms appear towards the end of the season. Getting aphids under control may also minimize virus infection to some degree.

Cucumber mosaic virus – symptoms include yellowish-green “mosaic” mottling on foliage or fruit and crinkled leaves. Photo by Gerald Holmes, Strawberry Center, Cal Poly San Luis Obispo, Bugwood.org.

Papaya ringspot virus – symptoms include wrinkled leaves and discolored, bumpy fruit. Photo by Mary Ann Hansen, Virginia Polytechnic Institute and State University, Bugwood.org.

 

Watermelon mosaic virus – symptoms include wrinkled leaves and geometric patterns on fruit.  Photo by Dorina Pitorac, European Plant Protection Organization.

Zucchini yellow mosaic virus – symptoms include blistered, wrinkled leaves and fruit with discolored bumps. Photo by University of Massachusetts Extension.

Fruiting Vegetables

Late-season aphid feeding is being observed in some solanaceous crops. Honeydew is a sugary liquid secreted by aphids and other sap-sucking insects (whiteflies, spotted lanternfly, etc.). Honeydew accumulation on crop foliage or fruit can lead to growth of sooty mold, which is a term for various genera of fungi that colonize the sticky exudate. Sooty mold does not render vegetables inedible, however, and can be readily washed off. 

Honeydew from aphids (and other sap-suckers) on plant leaves is sticky to the touch and can be colonized by sooty mold. Photos by Kansas State University Entomology (top) and Joe Boggs, the Ohio State University Extension (bottom). 

Regular bouts of rainfall as we head into the fall are leading to increased incidence of Phytophthora infection in peppers (and cucurbits). While excess water is a problem for some vegetable growers in Ohio, some parts of western Ohio still remain abnormally dry, according to the U.S. Drought Monitor. Mites have been a problem in some areas, while thrips have taken a downturn. Keeping mites under control towards the end of the season can reduce the chance of heavy pressure next season by reducing the egg load/number of overwintering adults that will become next year’s mite infestations.

Fruit

Tree fruits

Early varieties of apples are being harvested across the state. Brown marmorated stinkbug pressure is increasing. Bitter rot is starting to be observed in some orchards. Marssonina leaf blotch is also being seen in some organic orchards, where management can be difficult without the use of fungicides. Removal/destruction of leaves on the orchard floor in the fall can reduce overwintering sites for the pathogen. Black knot is being seen on some ornamental plum trees, so commercial plum and cherry growers should keep an eye out for black knot galls on their trees and promptly remove them if they see them.

Gall of black knot (Apiosporina morbosa), a fungal pathogen of plum, cherry, and other types of fruit trees. Photo by Joseph O Brien, USDA Forest Service, Bugwood.org.

Small Fruits

Preparing Brambles for Winter – Sanitation Practices for Disease Prevention
Melanie Ivey, State Fruit Pathologist and Fresh Produce Safety Specialist, The Ohio State University

Disease management of perennial fruit crops is a year-round endeavor. Many fungal pathogens survive the winter months in the soil or plant debris, infected canes or buds, or dead canes. As part of an integrated disease management program fall sanitation practices to reduce inoculum in the planting should be done.  Best sanitation practices include removing floricanes after harvest, removing diseased and dead canes, removing dead or systemically infected plants, and raking or chopping fallen leaves. Pruning debris should be destroyed by burning or placing in the trash or discarding it away from the planting. Diseased plant material should not be composted.  Pruning cuts should be sharp and clean to avoid unnecessary mechanical wounds.

The fall is also a good time to scout for and remove wild bramble populations that are near the production field. In addition to fall sanitation practices, some diseases require a dormant or delayed dormant fungicide application. For dormant or delayed dormant fungicide recommendations consult the Midwest Fruit Pest Management Guide (OSU Extension Bulletin 506).

The table below summarizes where the fungi for several common diseases of brambles in Ohio overwinter, the recommended fall sanitation practices for each disease, and whether a dormant or delayed dormant fungicide application is recommended.

Upcoming Events: 

September 19 – 21, Farm Science Review

September 27, Wooster, OH, Midwest Mechanical Weed Control Field Day

September 30, Albany, OH OEFFA CSA Veggie Farm Tour

December 5th – 7th, Grand Rapids, MI, Great Lakes Fruit, Vegetable, & Farm Market Expo 

January 15 – 16, Columbus, OH, 2024 Ohio Produce Network

February 15 – 17, Newark, OH, 2024 Ohio Ecological Food and Farm Association (OEFFA) Conference

Avoiding Problems Associated with Too Much of a Good Thing

Just like folks who wish for rain or look for irrigation during dry times, growers experiencing more than optimal rainfall look for ways to handle soggy conditions.

Rain is obviously good but too much of it can be a huge headache or worse. While rainfall in some areas has been just about right in recent weeks, rainfall in other pockets of Ohio vegetable production has become troublesome lately.

Open field growers can prepare only so much for excess rain, especially when it falls in large amounts over short periods of time. However, predictions indicate that doing what is possible to prepare for deluges will be useful. Five steps familiar to most experienced growers because they always support positive production outcomes – not just during wet periods or seasons — can help.

1. Use a set of varieties ranging in maturity and seed/transplant multiple times (stagger plantings). This helps manage workloads, blanket market opportunities, and distribute risk since individual plantings will be at different stages in development when dry, wet, or other unwelcome conditions occur and, therefore, possibly be less affected by them.
2. Select naturally well-draining fields whenever possible. Fields that tend to hold moisture may be a blessing during dry periods but a problem during wetter ones. Assuming irrigation is available, naturally well-draining fields are likely to be more reliable across seasons.
3. Improve and maintain the site’s drainage, i.e., its capacity to withstand and “process” excess rain. Grade, tile, and employ rotations and soil management and production practices proven to limit the site’s potential to flood and for saturated conditions to persist.
4. Use appropriate crop-specific tactics to manage beds or hills from the start of each production cycle. Potato, Cucurbit, and other crops are often in direct contact with the soil. So, they can benefit from hills and beds being set and managed as if flooding is a real possibility.
5. Prepare for harvest in advance. Advanced preparation can help ensure it will be possible to harvest sooner than expected, if possible and needed.

Mid-Late Season Check of Fertilizer Programs: Are They Right?

Four Rs are the cornerstones of successful fertilizer application: the Right Material, applied at the Right Time, in the Right Amount, and to the Right Place. In the last several weeks, troubleshooting with growers and others about under-performing squash, sweet corn, tomato, and watermelon crops led us to conclude that incorrect fertilizer application rates were probably to blame. The information available suggested that too little fertilizer had been applied to the squash and sweet corn while too much had been applied to the tomato and watermelon plantings.

Ohio growers produce many different vegetable crops, each with a farm-specific fertilizer program that is best or most “right” for them. Very important, those fertilizer needs are set by the biology of each crop and its growing conditions and market. Crops, growing conditions, and markets are diverse, and that calls for setting and monitoring fertilizer applications very carefully; material, timing, rate, and placement must be optimal to have the best chance of success.

Errors at each step in the application process from selecting the rate to applying the material can lead to under- or over-applying fertilizer. For example, target rates can be miscalculated. Hoppers and injection tanks can be under- or overloaded. Gears, valves, and other equipment can be poorly calibrated or malfunctioning. Applicators/spreaders can be driven over too much or too little ground. Irrigation and/or injection valves can be closed when they were supposed to be open or vice versa.

Overall, some appear to worry less about applying too much instead of too little fertilizer. Their desire to maximize yield and quality is understandable. That said, the consequences of significantly over-applying fertilizer should also be considered since they may be wider ranging and last longer. Applying too much fertilizer in one season can create the problems of under-application in that season (lost yield, quality, and income) while also complicating fertilizer programs in the following season(s), supporting unwanted changes in soil chemistry, and contributing to other issues. Benefit the most from investments in properly selected fertilizers by applying them at the right rates and times and to the right place.

Impacts of Drought on Vegetable Production and Potential Solutions

Much-needed rain on Sunday has given agricultural producers some reprieve from the “flash-drought” that has been building across Ohio over the past few weeks. Ohio has seen abnormally-dry to moderate-drought conditions across much of the state, according to the U.S. Drought Monitor. The Ohio State University College of Food, Agricultural, and Environmental Sciences (CFAES) has activated its Rapid Response Team to address the dry weather and provide extension resources for agricultural communities, including commercial vegetable producers. More information can be found at the OSU Early Drought Response webpage.

Periods of drought have plagued humanity since agriculture began. In modern vegetable production systems, dry conditions can lead to issues at multiple levels. This article will unpack the impacts of drought on vegetable production and discuss possible solutions.

 

Crop moisture stress

Crops vary widely in their water use efficiency (WUE), i.e. the amount of carbon produced per unit of water taken up by the plant. Many grain crops have been specifically bred for high WUE to maintain productivity in dryland systems. Vegetable crops, on the other hand, have comparatively low WUE and are typically irrigated via drip tape or center-pivot. Due to their higher water needs in “normal” seasons, many vegetable growers are already set up for irrigation and so may not be witnessing as severe crop moisture stress as field crop growers who rely on the rain.

Heat stress

In addition to the lack of rain, temperatures in northwest Ohio climbed into the high 80s near the end of May. High temps can threaten young plants in other ways apart from increased water demand. When crops are transplanted into black plastic mulch they can be stressed by heat radiating off the mulch surface. Young plants can also be burnt if any plant tissue is contacting the black plastic, which may be common if soil moisture levels are below wilting point. Transplanting into wet soil, overhead irrigation, or applying kaolin clay to plastic mulch surfaces to temporarily increase sunlight reflection can help keep temperatures around the plant cool and conducive to crop health.

Dry weather pests

Hot, dry weather in the spring can lead to earlier and increased activity in plant pests like thrips, aphids, and spider mites. These insects thrive in warm and dry conditions, which is why infestations in greenhouse environments are common. Insect feeding can reduce crop yield and quality and the pests can also vector viruses that affect vegetable plants.

Outbreaks of thrips, aphids, and spider mites can be managed in part by supporting natural enemies of the pests. These include ladybeetles (adult and larvae), lacewing larvae, and minute pirate bugs. Aphids are also preyed upon by damsel bugs, assassin bugs, aphid predatory midges and several predatory wasps. Species of predatory thrips and mites can also help keep pest thrip and spider mite populations in check. Find information on identifying natural enemies in this guide from OSU Extension and this educational video from Dr. Mary Gardiner at OSU.

Insecticide/miticide recommendations can be found in the 2023 Midwest Vegetable Production Guide. Avoid broad-spectrum products to conserve natural enemy and pollinator populations in the field. Read more on the topic in this article from Zsofia Szendrei at Michigan State University.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Pests that prefer hot, dry conditions: aphids (top), thrips (middle), and spider mites (bottom). Photos by University of Illinois Extension (top), Ontario Ministry of Agriculture, Food and Rural Affairs (middle) and Mississippi State University Extension (bottom).

Weed control

Drought conditions also have implications for early-season weed control. With low moisture in the topsoil, weed emergence may be delayed and prolonged. Applying layby residual herbicides is important to keep weeds under control until canopy closure. Weeds that are heat/drought stressed also do not respond to postemergent spray applications as well as vigorous weeds. Plant leaves develop a thicker, waxier cuticle to minimize water loss which can also reduce herbicide absorption. Adjuvant usage may be needed to improve conditions for herbicide uptake. Weed growth and metabolism is also slowed, which reduces movement of systemic herbicides around the plant. Spraying in the morning can be advantageous for weed control, not only because of calm winds, but also because targeting plants at a time of day when they are the least heat stressed can improve performance of systemic herbicides. Read more on this topic in this recent article from Erin Burns and Christy Sprague at Michigan State University.

Wildlife damage

 Wildlife damage to crops can be worsened in hot, dry weather. Rodents and other vertebrates may increase feeding in vegetable fields when food and water is scarce elsewhere. Irrigation equipment may be damaged by wildlife (coyotes, mice, etc.) looking for a drink. Options for keeping away wildlife include netting, fencing, repellants, trapping, and other lethal/non-lethal deterrents. Resources include the Ohio DNR Nuisance Animal Control Manual and Wildlife Management Factsheets from the USDA/Michigan State University Extension.

Farm safety

Last but not least, the safety and well-being of agricultural workers is important to keep front of mind. Working in hot and dry conditions poses a risk of heat-related illnesses. Continuous hydration and proper attire can go a long way towards ensuring worker safety. Find more information on the major heat-related illnesses and their mitigation in this article from Penn State.

Dealing with drought-stressed crops and dusty fields can also take a toll on growers’ mental health. Ohio State University Extension offers resources to help handle farm stress. Farm worker/manager performance is dependent on good mental health, so be sure to take this aspect of your vegetable operation seriously.

To sum it up, hot and dry conditions impact multiple aspects of vegetable production. While the material here mainly addresses the consequences of a dry spring, drought can cause different issues depending on when in the growing season it occurs. OSU Extension is a resource to help vegetable growers through periods of drought by providing information and support. Please reach out to your county educator or a vegetable extension specialist to explore ways OSU Extension can help you make your vegetable operation more resilient to drought conditions.

Thank you to Ben Werling and Ben Phillips from Michigan State University Extension for observations and ideas that contributed to the writing of this article.

Chris Galbraith

Vegetable Extension Educator

Northwest Ohio
Ohio State University Extension
Office: 734-240-3178
galbra53@msu.edu

Six Factors to Consider Given the Dry Season So Far

Although some areas of Ohio have received small but timely amounts of rainfall, the general lack of it across the state to this point in the season has become a concern, especially where dryland, non-irrigated crops are stake. As one example, according to one weather station at the OSU campus in Wooster, rainfall for the period May 15, 2023 – June 10, 2023 was the lowest on record for the same period since 1999 and roughly half the amount received during the same period in the previous driest year. Not surprisingly, stand establishment in a non-irrigated potato planting made on May 15 at the research station in Wooster has been much lower and slower than normal.

On the other hand, overall conditions for many irrigated crops have been acceptable, minus the damaging early season frosts and windstorms. Temperatures have been moderate for the most part, so damage due to the lack of rain has not been significantly compounded by problems associated with high temperatures. Also, a lack of rain can maximize the amount of time available to complete other work — although many would gladly trade some time for rain.

Indeed, dry conditions to date have interfered with crop establishment and development and other aspects of production, particularly where irrigation is not being applied. So, we welcome forecasts including a high probability of meaningful rainfall.

This article references six items to consider if rainfall begins to “even out” in terms of timing and amount.

1. Continued crop thirst. Irrigation tends to be beneficial in all but the wettest years. Even short periods of low water stress can damage crops. Therefore, those who have been irrigating or begin to irrigate may need to continue the practice until harvest, in accordance with rainfall amounts and other factors, per usual.

2. Nutrient availability. Dry fertilizers applied before, at, and/or soon after planting may begin to solubilize more completely, boosting nutrient availability. In-season applications may need to be adjusted to account for this increased availability, although later than planned. Consider in-season soil, tissue, and/or sap testing to assist in the process.

3. Weed control, particularly as affected by herbicide activity. Dr. Lynn Sosnoskie of Cornell University summarized this issue well in the June 7 edition of the Cornell Cooperative Extension VegEdge Newsletter. Contact Dr. Sosnoskie (lms438@cornell.edu), the Cornell Vegetable Program (cce-cvp@cornell.edu), or me (Matt Kleinhenz; kleinhenz.1@osu.edu) for a copy of the article, which summarizes factors to consider for weed control during extended dry periods and should rains resume.

4. Crop protection, especially disease. Soil moisture, nutrient availability, and weed growth may increase if rains begin and so may disease pressure. Crop protectants, application schedules, and other tactics may need to be adjusted to account for increases in leaf wetness periods, relative humidity, and, perhaps, disease inoculum levels.

5. Soil erosion. Ideally, this dry period will be broken by grower-friendly light rains capable of providing the most benefit with the least trouble. However, soil erosion is possible if rains are brief and heavy and fall on uncovered, unprotected soils. If possible, use the dry period to check, improve, and explore drainage systems and soil management tactics.

6. Crop growth and harvest readiness. The best-laid plans set before the season call for seeding and transplanting to occur on farm-specific schedules, partly to meet harvest timing and market goals. Following through on those plans is difficult under dry conditions since they slow growth and alter maturation schedules. For example, for fruiting vegetable crops, a rule of thumb has been that drought before flowering speeds maturation while drought after flowering can slow it. Regardless, early-season dry conditions followed by more normal rainfall patterns can complicate maturation timelines across plantings (early, mid, late) and variety maturities. So, monitoring and flexibility remain important.

Growers, Grafters, Researchers, and Extension Partner in Identifying Best Management Practices for Grafted Vegetable Plants – Watermelon in Ohio in 2023

Many growers know that grafting gives them access to much needed disease resistance – stronger resistance to some diseases than available in hybrids and more resistances than often found in them, too. Indeed, a quick scan of rootstock characteristics at http://www.vegetablegrafting.org/resources/rootstock-tables/ reveals that few commercial hybrid varieties of tomato or watermelon include some resistances found in rootstocks. However, the greater cost of grafted plants has many people asking how growers’ profits can be maximized when using them. Lowering costs and boosting yield and quality are key parts of the answer.

Best Management Practices (BMPs) are “how-to” guides used in commercial crop production. BMPs are developed over years of collaboration involving many people since they involve optimizing every aspect of individual production systems from site and variety selection through post-harvest handling, packaging, and delivery. Current vegetable BMPs are based on the use of nongrafted plants. However, grafted plants tend to be more vigorous than and different from nongrafted ones in other ways. More important, perhaps because of these differences, grower and researcher experience with grafted vegetable plants indicates that farm BMPs must be updated to lower the costs and maximize the grower profits associated with using grafted plants. Optimizing plant density (number of plants per acre based on in- and between-row spacing), and irrigation, fertility, and harvest management for many scion-rootstock combinations has become the focus of much on-farm and on-station research.

Four Ohio farms, The OSU North Central Agricultural Research Station (https://oardc.osu.edu/facility/north-central-agricultural-research-station), and OSUE will evaluate the effects of plant density using four scion-rootstock combinations in 2023. Drawing on previous work (e.g., https://u.osu.edu/vegnetnews/2021/08/21/grafted-watermelon-plants-under-what-conditions-and-practices-does-using-them-offer-the-best-return-on-investment/), plants provided by Tri-Hishtil of Mills River, NC (https://www.trihishtil.com/) will be set at a range of in- and between-row spacings affecting potential grower costs and, possibly, fruit maturation, yield, and/or quality. Within and across sites, the total plant population is expected to equal roughly 450 – 1,450 plants per acre in individual plots. The team is intrigued by the possibility that yield and quality will remain high in some treatments/plots although many fewer plants, rows, and various inputs will have been used.

We would like to hear from you if you have questions about making and/or using grafted vegetable plants or information on the topic. Please contact Matt Kleinhenz (kleinhenz.1@osu.edu; 330.263.3810).

Successful Production Begins with the Best Varieties: An Example from Potato Breeding

If you grow potatoes for profit, chances are you rely on varieties developed by a university-USDA-industry team dedicated to improving your success by improving the varieties available to you. This article outlines aspects of that process and The OSU’s participation in it in 2023, as in more than fifty previous years.

The overwhelming majority of potato varieties used in Ohio and the U.S. are developed by university- and USDA-based programs and teams. These teams are led by breeders-geneticists and include plant pathologists, entomologists, food scientists, horticulturalists, and others working closely with growers, grower organizations, processors, retailers, seed certification programs, and members of industry and government. The small number of teams in the U.S. are based in major production regions, e.g., Northwest North-central, and East, allowing them to develop varieties best suited to these regions. The OSU has cooperated with the Eastern team with breeding programs in Maine, New York, and North Carolina and partners in other states for more than fifty years (see https://neproject.medius.re/ and potato reports at https://u.osu.edu/vegprolab/technical-reports/). The OSU also collaborated with the North-central team with breeding programs in Michigan, Wisconsin, Minnesota, and North Dakota for more than forty years. Regardless of team, working from industry and consumer input, our goal has been to improve marketable yield regardless of production constraints (e.g., disease, nematode, abiotic stress), tuber quality (including sensory properties and nutritional value), crop use of natural resources (e.g., water, fertilizer) and other characteristics. Efforts completed here continue to benefit growers, processors, retailers, chefs, consumers, and others in Ohio and throughout the Eastern U.S.

Potatoes are clonally propagated – i.e., tubers are clones of their mother plant. This means that increasing the availability of seed for a new superior variety can be more straightforward than in crops requiring true botanical seed. However, in its early stages, potato breeding requires creating and evaluating experimental lines resulting from ‘hybridizing’ crosses, e.g., as in tomato variety development. Many crosses are unproductive while others result in experimental lines worthy of additional evaluation under a wide range of conditions. That is when a network of collaborating evaluators operating in various environments where the experimental line/new variety could be grown commercially becomes essential.

In 2023, The OSU will evaluate 126 experimental selections against 12 standard varieties. As before, selections from the University of Maine, Cornell University, USDA-ARS in Maine, and North Carolina State University will be featured and our evaluation process will focus on the interests of growers, processors, retailers, chefs, and consumers. Plots are located at the OSU-Wooster/OARDC and can be viewed anytime. If possible, please contact Matt Kleinhenz ahead of time so he can welcome you properly and help you benefit fully from the tour (kleinhenz.1@osu.edu, 330.263.3810). Also, seed is available to growers who wish to evaluate experimental selections on their farms.

A subset of the information that will be collected for each experimental line through November-2023 is listed below.

Before Harvest
1. Percent stand (# seed pieces planted versus number of plants established)
2. Plant maturity
3. Tuber bulking period
After Harvest
4. Total yield
5. Percent tubers greater and less than 2 inch in diameter
6. Percent of tubers that are misshapen or have a similar market defect
7. Basic tuber characteristics (9 options for each of the following six characteristics – 531,441 possible combinations!): a) skin color, b) skin texture, c) shape, d) flesh color, e) eye depth, and f) uniformity
8. Tuber internal quality (incidence of defects)
9. Specific gravity
10. Chip quality (color, blister), including as chipped directly after harvest or storage (with or without reconditioning). Chip-stock production in Ohio is mainly for situations in which crops are chipped directly after harvest with no storage period.

Regardless of market, on all but a small set of operations, potato vines are removed before harvest either mechanically (quickly) or chemically (slowly). How vines are removed is important to growers and all members of the potato value chain. They all want tubers well suited to a specific end use; however, some varieties may respond less desirably to quick, mechanical vine killing, especially if vines have not died naturally or are not actively senescing. Applying a desiccant that kills the vines slowly and promotes tuber skin set and stolon detachment is most common. However, some growers may choose or be required to harvest crops “green,” when vines have not died or have been chopped very recently, a typical approach to mechanical vine killing. Importantly, vine killing methodology can affect the condition of the tubers at harvest and after, during processing, storage, shipment, and preparation. Killing vines quickly and harvesting soon after can influence various tuber properties including: a) stolon attachment, b) skin integrity/scuffing, c) physical damage, d) relative abundance of starch versus reducing sugars, e) incidence of bruises, and f) storability. Buyer and grower tolerances for these issues can be low so identifying lines capable of being harvested “green” and used effectively can be important. Of course, some consumers prefer small “new” tubers with very thin skins so these crops must be handled carefully. Similarly, growers and processors are also keen to discover the optimal storage conditions for experimental lines and new varieties and the extent to which their tubers must be “reconditioned” before use as referenced in https://www.potatogrower.com/2019/03/top-5-factors-to-successful. Through the years, once popular processing varieties were displaced by new ones with less stringent storage-reconditioning requirements, a discovery made during collaborative testing by variety development teams and industry.

As always, the 126 experimental lines will also be evaluated for their resistances to multiple diseases, nematodes, and insect pests by other team members in Maine, New York, Pennsylvania, Virginia, North Carolina, and Florida. Cooking and consumer evaluation tests will be completed.

Information that will be collected before and after harvest is key because plant and tuber characteristics and yield strongly help determine the main end use and market for which a variety is best suited: a) general fresh market, b) specialty fresh market, c) processing (e.g., chip), or d) fresh-processing dual purpose. Of course, this also means the same variety profile also determines which farms and farmers will benefit most from using a new variety. Production for chip and direct-retail markets has increased in Ohio in recent years.

As shown earlier (see https://u.osu.edu/vegnetnews/2023/03/11/how-will-your-yield-and-efficiency-increase-this-season/), U.S. potato yields have climbed steadily for more than a century. This increase is due to better varieties and crop management. Regardless of your market, if potatoes are part of your business, it can be essential to watch for and test new varieties since they provide the greatest reward for your high-level skill as a grower. As much as possible, take advantage of that skill by using superior varieties instead of relying on it to overcome weaknesses of inferior ones. Future related articles will provide information specific to obtaining seed for new or “alternative” varieties that may benefit your business.