Season Extension is when a vegetable, herb or fruit is grown outside its normal growing season using protection from the elements in some way. While it is most commonly used over the winter to take advantage of Ohio’s four seasons of growing, it is also applicable in summer when growing vegetables that prefer cooler weather. A part of the community garden plot opened up after cucurbit production decreased from cucumber beetle damage and bacterial wilt.
Was planted with zucchini and cucumbers from mid-May until late July
The plasticulture fabric was removed, the soil was amended with slow release granular fertilizer and compost, It was then planted with lettuce and pac choi cabbage transplants that had been started under the lights 3 weeks ago. The cucurbits were productive heavy feeders so extra fertility was needed, especially in the form of nitrogen, and crop rotation was observed among different vegetable families.
The wood form is 4′ x 8′ in size and 4″ high tall made of untreated wood. The PVC is 1/2″ in diameter and sleeved onto screws. This allows easy use of season extension in a defined space that keeps the fabric off the plants, but is very stable to the elements.
The raised bed form was then covered with shade fabric. This fabric is designed to allow light, air, and water to pass through, but to decrease the amount of sunlight and provide shade to the cooler temperature season lettuce and cabbage during the August maturation period. Multiple other vegetable crops could be grown with this method including radishes, spinach, arugula and other small brassicas.
30% sunlight reduction shade fabric. In most cases this fabric should be vented to allow air movement and prevent heat buildup under the fabric. It is shown closed in this picture to prevent small mammal feeding damage overnight, but will be clipped part way up the PVC tubing during the day normally.
This fabric will provide protection from the cabbage white butterfly and its associated larval form that feeds heavily on the foliage of brassica family crops. This means it also will not allow pollinators to enter the space if it is kept fully closed. This is not a concern as both the lettuce and cabbage will be harvested before they flower and produce seed and have no need for pollinators.
The use of shade fabric for season extension allows harvest of cool weather crops that are otherwise difficult to grow in mid-summer. The element and insect protection from the fabric allows for a higher quality crop. An off season, high quality crop has the potential to demand a higher price in a CSA subscription or at the Farmer’s Market booth. The fabric is available in multiple lengths and widths to allow scale up to larger sized production areas if needed.
Make sure to incorporate season extension methods when making your garden plan. Ohio is a true four season growing environment and with some planning and using season extension, harvest can be achieved all year long.