By: Scott Eckert, County Extension Agent, Horticulture
It?s July so let?s talk about fall gardening! Fall is an excellent time for gardening in Kansas. A supply of fresh vegetables late in the year ex-tends the gardening season, and the quality of many vegetables is better for fresh use and preserving. Many vegetables can be left in the garden and used as needed into the winter months.
What to plant
Space available and preference will influence the choice of crops to plant for fall production. With attention to watering and pest control, many vegetables that are already growing in the garden will continue to produce into the fall months. Some of these crops are tomatoes, okra, peppers, New Zealand spinach, eggplant, and sweet potatoes. Crops that are best adapted to fall culture are mainly the cool-season crops, although cucumbers, summer squash, and beans can be grown as fall crops. Most spring vegetables are adaptable to fall gardening, but many Kansas gardeners report little success in growing fall peas. Peas require cool temperatures for germination and do not seem to adapt to the warmer temperatures of the summer planting period. You may want to try snow peas–in a mid-to-late August planting, but don’t expect complete success. Cabbage, broccoli, cauliflower, and Brussels sprouts make excellent fall crops. Plant seed rather than transplants. When young plants are 0.5- 0.75 inch tall, thin them to one plant per foot of row. Beets and carrots require adequate moisture until they emerge. A light cover of sand or compost over the row may prevent soil crusting and improve emergence. Freshly cut potato seed pieces will rot easily in warm summer soils. Seed should be cut 3-4 days
prior to planting and held at room temperature to heal over. This will prevent seed piece decay. Various types of lettuce may experience a marginal leaf burn with a light frost. The center leaves may escape damage, allowing lettuce– especially bibb or head–to remain past the
first frost forecasted.
When to plant
Planting dates are influenced by how long it takes the crop to develop and how tolerant the crop is of first frosts or freezes. Crops such as potatoes or cabbage require a long period of development, thus a mid-July planting date, while crops such as lettuce or radishes can be planted in early September. The average first frost in the fall occurs in mid- October in most of central Kansas.
Fertilizing and soil preparation
Planting in space used for spring production may require additional fertilizer to support fall crops. In general, 1-2 lbs/100 square feet of a low-analysis, all-purpose garden fertilizer
should be sufficient. Although adding organic matter is an excellent practice, it is not a good idea to add quantities prior to fall planting because this may loosen and dry out soils at a critical time. Save your organic matter for a late fall application. Extensive soil preparation probably will not be needed for fall planting. Avoid deep tillage because it may dry out soil moisture. A light surface cultivation will loosen the soil to prepare the seedbed. Additional amounts of fertilizer may be needed later in the season to ensure maximum plant growth and production.
Cabbage, broccoli, cauliflower, collards, and kale, plus lettuce, mustard, spinach, and turnip greens will require about 4 tablespoons of a high-nitrogen all- purpose garden fertilizer per 10 feet of row. It should be sprinkled along the row about 2 weeks after transplanting, or 4 weeks
after sowing the seed. This will ensure lush vegetative growth prior to crop development during the cooler fall weather. Other vegetable crops probably will not require any additional fertilization.
Establishing vegetables in summer heat
Fall gardeners will find that establishing a garden during the summer when soil temperatures are extremely high is difficult. One way to avoid seeding in extremely adverse conditions is to
establish plants in containers or pots for transplanting to the garden later in the season as the weather begins to cool. Crops such as cabbage, broccoli, cauliflower, Chinese cabbage, and collards can be grown in a cooler protected area, or under lights in a basement growing area for 2-4 weeks prior to setting in the garden. Place the flats in the direct sun, and providing adequate water for 2- 4 days to allow the plants to become accustomed to the stronger winds, hot sun, and the harsh environment of the summer garden. Crops that are seeded directly should be planted slightly deeper than they would be for a spring garden. This has two benefits; it provides a slight cooling effect, as well as more moisture available at the deeper soil depth. It is probably wise to plant more seed than necessary, and do some thinning later to ensure an adequate stand.
Many areas of the state receive adequate rainfall for successful gardening from late August through September and October. However, trying to establish young seedlings in high temperatures during July to mid-August is difficult without a readily available source of water. Many vegetables can develop a tolerance to a hot temperature, but they cannot tolerate a lack of sufficient soil moisture and cannot germinate without it.