Plant Fall Vegetables Now

Time for Fall Vegetable Garden is Now

Tom Ingram: Ask a Master Gardener

Tuesday, July 4, 2017

Q: I want to try a fall vegetable garden this year. What does well here in Oklahoma and when do I plant? N.J., Tulsa

A: For those of us who love the taste of fresh fruits and vegetables, gardening is a year-round activity. The fall gardening season, which begins around July 15, can actually produce some of the tastiest garden vegetables in northeast Oklahoma, as we typically have warm sunny days followed by cool nights. Under these conditions, plant metabolism slows down, which helps produce high-quality and tasty vegetables.

Vegetables grown in fall gardens can be divided into two categories: tender vegetables, which need to be harvested before the frost, and semi-hardy vegetables that can continue to grow and be harvested through several frosts.

Examples of tender vegetables would be beans (bush, pole, lima), cilantro, corn, cucumber, eggplant, pepper, pumpkin, squash and tomatoes. Semi-hardy vegetables would include beets, broccoli, cabbage, carrots, potatoes, kale, lettuce, peas, radish, spinach and swiss chard.

The brutally hot temperatures we often have in July and August demand we pay special attention to any vegetables we intend to direct seed in our fall gardens. As a rule, seeds should be planted no deeper than three times the diameter of the seed. With small seeds, such as carrots, this would mean planting no more than 1/4-inch deep. At these depths, hot soil temperatures will discourage germination. Supplemental watering or perhaps shade cloths will be needed to reduce soil temperatures so germination can occur.

The good news is many of our fall vegetables can be started from seed indoors, which helps us avoid having to deal with the soil temperature issue. Plants that perform well as transplants include cucumbers, squash, peppers, pumpkins and tomatoes. Before moving transplants into the garden, they should be conditioned or toughened by reducing watering and exposing them to full sunlight in limited amounts.

If space allows, potatoes are also a wonderful fall garden crop. Seed potatoes need to go in the ground the first two weeks of August to complete growing before the first freeze.

The first of September is the time to plant garlic, leeks and onions, as they will continue to grow through the winter for a harvest in late spring the following year.

We have several fact sheets from OSU, which not only provide you with the planting dates for fall crops but also contain recommended varieties of vegetables that can be grown successfully in Oklahoma. Just give us a call, drop by our office, or check our website, tulsamastergardeners.org. We are here to help.

You can get answers to all your gardening questions by calling the Tulsa Master Gardeners Help Line at 918-746-3701, dropping by our Diagnostic Center at 4116 E. 15th Street, or by emailing us at mg@tulsamastergardeners.org.

Garden tips

• Vigorous, unwanted limbs should be removed or shortened on new trees. Watch for forks in the main trunk and remove the least desirable trunk as soon as it is noticed.
• Most varieties of mums are more productive if “pinched back” now. Either pinch off with fingers or cut to remove an inch or so of limb tips above a leaf. This results in the growth of new limbs and a fuller plant. Do not pinch after mid-July or it will interfere with fall blooming.
• Watch for tiny, sap-sucking insects called aphids on roses, perennial flowers, shrubs and vegetables (especially tomatoes). They produce a sticky substance called “honeydew.” Many can be dislodged with a hard spray from your garden hose, or two applications of insecticidal soap will usually greatly reduce any aphid damage to your plants.
• Crape myrtles are one of the few shrubs that should be planted in the middle of summer. Growth of new roots of these plants occurs best with summer soil temperatures.