It’s late March and I have yet to harvest a single spring pea or leaf of spinach, but it’s already time to start planning for the summer kitchen garden. I don’t know about you, but I’m eager to enjoy some homegrown, fresh vegetables. I want to be ready as soon as the conditions are right to plant my favorites such as tomatoes, corn, and okra.
These plants are a few of what are referred to as warm season vegetables that require long days and warm temperatures to thrive. Unlike spring varieties such as lettuce and broccoli, warm season vegetables sulk in cold soil and can’t tolerate a frost. They also need longer periods of sunlight.
Warm season vegetables should be planted in the garden after the last frost date in your area. This is an estimated date for when the threat of freezing temperatures has passed. The soil should also be warm enough for seeds to germinate or, if your using plants, roots to grow.
It’s also important to know the FIRST frost date in your area so you can determine if your growing season is long enough for plants to mature and bear fruit. Seed packets and plant containers will list maturity dates for plants.
Below is a chart with average dates based on zone. These will differ slightly year to year but they give you a basic window of time in which you can create a planting schedule.
|ZONE||AVERAGE LAST FROST DATE||AVERAGE FIRST FROST DATE|
|Zone 3||1 May / 31 May||1 Sep / 30 Sep|
|Zone 4||1 May / 30 May||1 Sep / 30 Sep|
|Zone 5||30 Mar / 30 Apr||30 Sep / 30 Oct|
|Zone 6||30 Mar / 30 Apr||30 Sep / 30 Oct|
|Zone 7||30 Mar / 30 Apr||30 Sep / 30 Oct|
|Zone 8||28 Feb / 30 Mar||30 Oct / 30 Nov|
|Zone 9||30 Jan / 28 Feb||30 Nov / 30 Dec|
|Zone 10||30 Jan or before||30 Nov / 30 Dec|
|Zone 11||Free of Frost throughout the year.|
You can get around a short growing season by starting seeds indoors early or selecting large sized plants, and planting varieties with early maturity dates such as ‘Early Girl’ tomatoes.
For those of you who enjoy an extended growing season you can plant a second crop around the summer equinox (June 21st or 22nd) for a late summer harvest. This is particularly nice if you want extra vegetables for canning or preserving.
Popular Summer Vegetables to Grow
|Autumn and Winter Squash – This is the thick-skinned cousin of summer squash. Acorn, butternut, delicata and pumpkins are all autumn/winter squashes. Vining varieties need plenty of space, at least 5 to 10 square feet per hill. Bush varieties can be planted in smaller gardens and only require 3 to 5 feet of room. These squash like full sun and well-drained soil. Allow them to ripen on the vine before harvesting at the end of the growing season before the first frost.|
|Bush Beans – Beans are super easy to grow from seed. Direct sow them in the garden after the soil temperature has warmed to 60 degrees F. Sow seeds every 3 weeks for a continuous harvest. Stop sowing about 8 weeks before the first fall frost date. Bush beans do not require staking. Beans are shallow rooted so be careful when working the soil around the plants.|
|Corn – Corn requires a lot of space to grow and the pollination must be just right. There are few vegetables that are as tasty fresh from the garden so it’s worth the effort. Corn relies on wind to carry pollen from the tassels to the silks on immature ears. To increase the chances of pollination it is best to plant corn in a square of short rows. Space plants about 1 foot apart. Feed at planting with a general organic fertilizer and again when tassels begin to form. Water consistently and regularly. Corn is shallow rooted so water diligently, especially during dry weather.|
|Cucumbers – Cucumbers need full sun, at least an inch of water per week, rich soil and pollinating insects to produce. Pick fruits regularly so that the vines will continue to produce. Bush varieties are suitable for containers, but if you have the space try vining types because they will produce more fruit. Just be sure to support vining cucumbers with a trellis.|
|Eggplant –Eggplant require lots of sunshine and warm, well-drained soil. Plants should be set out about 3 weeks after the last spring frost. Gardeners in warm climates with long growing seasons can direct sow seeds in the garden at this time. In cool regions seeds should be started indoors 8 – 10 weeks early and planted in containers where the soil temperature is warmer than the ground soil. In spite of their love of heat, once in the garden, eggplants like cool, moist roots. Mulch the ground with straw and keep it moist but not soggy.|
|Okra – Okra loves hot weather, rich soil and full sun. It should be direct sown in the garden several weeks after the last spring frost. In spite of this plant being considered a Southern vegetable, it can be grown in cooler climates. Seeds should be started indoors and moved out into the garden after the summer equinox in late June. Treat them like your mother’s best china when you plant seedlings because the roots are very delicate. Pick pods when they become 3 to 4 inches long. If they are allowed to over mature, the plants will stop producing. The over-ripe, tough pods are great for adding interest to cut flower arrangements.|
|Peppers – Wait a week or two after the last frost date to plant peppers. Give them full sun, well-drained soil and consistent moisture. Feed with an organic fertilizer after the plants begin to flower and set fruit. Sweet peppers and bell peppers planted in hot climates may not begin to produce until weather cools in late summer.|
|Summer Squash and Zucchini – Squash does not transplant well so it is best to direct sow it in the garden after the last frost date or select plants in biodegradable peat pots that can be planted along with the squash. Summer squash prefers nutrient rich, well-drained soil. Prepare your beds before planting with a generous amount of compost or well-rotted manure and an application of an all-purpose fertilizer such as 13-13-13. Gather squash when they are young and tender. Old, large fruits with tough skins should be removed from the vine and thrown away. This will encourage more flowers and fruit.|
|Tomatoes – Tomatoes grown from seed should be started indoors 5 – 6 weeks before the last spring frost. Set the plants out when the soil has warmed and night temperatures stay above 50 degrees F. Tomatoes need 6 to 8 hours of full sun. Get your stakes or trellises in place when you plant. Plant tomatoes deep; bury at least two-thirds of the plant’s stem. This will give the plant strong roots and better fruiting. If the plants start looking worse for wear toward the end of summer, cut back and fertilize for a new flush of growth.|