Lack of rainfall, prolonged record heat, and drying windy weather can create drought-like conditions in gardens and landscapes. As the temperatures continue to rise it is always good to have a watering plan.
TREES, SHRUBS, PERENNIALS – Think about watering those permanent plants first. These include newly planted woody trees and shrubs; they need a thorough soaking throughout their root zones approximately once a week, assuming it has not rained that week. Newly planted perennials, rosebushes, and perennial vines also require attention. Water the base of plants to avoid getting leaves wet and reduce foliar diseases. Consider the use of soaker hoses or drip irrigation. Water deeply and less often to promote deeper, healthy roots. Add 2-3 inches of inches of shredded bark to the root zones of trees and shrubs to keep valuable moisture from evaporating. Mulch perennial or mixed borders with finely shredded material or compost that retains moisture and improves soil texture.
LAWNS-Although all plants need water to be healthy and grow, some—like lawns—actually need less water than we thin. Turf grass can go dormant. It will turn yellow, but the crown of the plants will remain alive with just ½ inch of water over several weeks. Grass will green up as soon as normal rainfall returns. Consider raising your mower height to 3-3.5 inches to result in a denser, healthier lawn. As small as they are, longer grass blades mean more photosynthesis and stronger, deeper grass roots. The grass blades also shade the grass crowns and soil, keeping them cooler during times of dry weather.
VEGETABLE GARDEN – The vegetable garden needs one inch of rain per week. By using a simple rain gauge or foll
owing weather reports, you can determine if your garden received one inch of rain over the past week. One inch of rain is a lot of water. For a 100 square-foot area, one inch of rain is 62 gallons. Figure out the actual size of your garden by measuring length and width in feet. Multiply those numbers to get total square footage. If a garden is 20 feet by 30 feet (600 square feet), after a week without rain, it would need 372 gallons of water.
You might receive rain, but not a full inch, over the course of the week. If it rained twice, but the total amount of rain was only three-eighths of an inch, you would need to supply the other five-eighths of an inch of rain. Five-eighths of 372 gallons is 232 gallons. Water gardens on sandy soils twice a week, supplying one-half inch of water (31 gallons per 100 square feet) each time.
HANGING BASKETS and CONTAINER PLANTINGS Containers can dry out very quickly. Daily or even twice-daily watering may be necessary. Feel the soil to determine whether or not it is damp. If the potting mix feels dry 1 inch below the surface, it is time to water. Apply water until it runs out the drainage holes. If the pot dries out too much you should immerse it in water to resoak the soil mix. Containers will need frequent checking as the plants grow and temperatures become hotter. Watering wands are good tools for difficult-to-reach baskets and window boxes. They extend your reach and produce a gentle shower.
Frequent watering flushes nutrients from the soil quickly, so frequent fertilizing is also necessary. Liquid fertilizers or timed-release fertilizers are the easiest methods of application. Time-release fertilizer pellets can be mixed into the soil at planting or worked into the top inch later. The soil in the container should be moist when fertilizer is applied, even liquid fertilizer. Feed baskets and boxes every two weeks from spring through summer with a complete liquid fertilizer diluted to half-strength.
Houseplants – If you have taken your Houseplants outdoors for the Summer, consider bringing them back indoors where their water requirements will diminish substantially.
WHEN TO WATER – Knowing when to water is key. Early morning to allow leaves to dry and reduce foliar diseases. Feel the top 6 inches of soil. Dry? Time to water. By watering in the morning, their foliage will have a chance to dry completely during the day before being moistened again from nighttime dew. Plants whose foliage never dries completely can develop mildew problems more quickly.
Some gardeners place a small can or other measuring gauge within the root zone of a tree so they can see when 1 inch of water has accumulated. The root zone is a circle that runs around the tree, extending from the trunk directly outward to the end of the lowest branch tips. The most effective watering devices are the slow soaker or drip hoses, plastic tree bags, or the small sprinklers that distribute water close to the ground, reaching the entire root zone.
Just knowing the what, when, where and how of watering in your garden or landscape is key to growing healthy plants and conserving our precious water supply.