If you want to bring in a bountiful and delicious harvest -- some might even say too bountiful at times! -- without much effort, growing summer squash is the way to go. Whether you choose long slender green zucchini, bright yellow crookneck, or something more unusual, these amazingly productive plants with reward you with plenty of tender squash to steam, bake, grill, or use raw in salads all summer long.
Green and Gold
There are three basic categories of summer squash to choose from when deciding what to plant -- straight neck yellow squash, crookneck yellow squash, and green zucchini. Within each category there are variations in size, shape, and color. Some varieties are hybrids, while others are open-pollinated. Hybrids offer traits like uniformity and long production, while many open-pollinated varieties have excellent old-time flavor and are a must if you'd like to save seeds. All are bushy, rather than vining, so they are a great choice for space-strapped gardeners. You can even grow summer squash in containers; use a pot that contains at least five gallons and is at least 10 inches deep.
The Long and the Short of Squash
Mention zucchini and most of us will think of a long, slender green vegetable. But there is more variety out there than that. 'Eight Ball', for example, is true to its name, producing small, round fruits that are perfect for individual servings. And zucchini is not always green. 'Gold Rush' is a hybrid with deep gold skin. So why not be adventurous and try something new along with the tried and true this summer. Here are just some of the great varieties we offer.
'Black Beauty' Zucchini (44 days) - This open-pollinated variety produces long, slender, slightly ridged fruits with black-green skins and delicately flavored white flesh.
'Summer Melody' Blend - This mix of open-pollinated varieties includes Golden Zucchini, Black Beauty, Grey Zucchini, and White Bush Scallop.
'Dixie' Crookneck (41 days) - This hybrid produces a dependable crop of high-quality lemon-yellow fruits that hold up well after picking.
'Fortune' Straightneck (39 days) - The vigorous plants are very productive, with a large harvest of attractive, dark butter-yellow fruits.
'Gold Rush' Zucchini (52 days) - The deep gold fruits of this All-America Selections winner are borne on an upright open plant that makes for easy harvest.
'Midas' Straightneck (53 days) - This hybrid offers resistance to powdery mildew, smooth butter yellow fruits, and excellent yield potential.
'Seneca' Zucchini (42 days) - One of the earliest varieties to bear, its fruits have excellent flavor and a small seed cavity.
Summer squash is easy to grow as long as you pay attention to a few basics. Start by choosing a spot in full sun with fertile, well-drained soil. Then wait until the soil is warm (at least 60 degrees F) and all danger of frost is past before planting the seeds of these heat lovers. Gardeners in southern areas (Zone 7 and south) can make several succession plantings over the course of the summer for a continued harvest. Northern gardeners can speed things along by using black plastic mulch both to warm the soil ahead of planting time and during the growing season to give these plants the warmth they thrive on.
Plant the seeds in rows or hills. To plant in hills, sow several seeds in a slightly raised mound about a foot across and thin to the two strongest plants per hill. Space the hills 3-4 feet apart. Follow the seed packet directions for row spacing.
Squash plants are heavy feeders, so give your plants a dose of soluble fertilizer such as fish emulsion every few weeks all season long. And make sure plants have a consistent supply of water, especially when they are blooming and setting fruits.
One of the biggest threats to your young squash plants is cucumber beetles. These black and yellow striped or spotted beetles not only feed on young seedlings, sometimes chewing them right down to the ground, but they can transmit deadly bacterial wilt disease as well. Covering seedlings with row cover fabric is an easy way to keep these pests from reaching your vulnerable young plants. Keep row covers in place until plants begin flowering, then remove them so bees can get in to pollinate blossoms. Be sure to seal the edges of the row cover fabric firmly to the soil so no insect intruders can sneak in.
Powdery mildew is a fungal disease that can affect squash plants across the country, covering the upper surfaces of the leaves with a white, powdery growth. Affected leaves may eventually wither and die. To combat this problem, choose varieties bred to have resistance or tolerance to this disease, handpick affected leaves as soon as you notice them, and clean up all crop debris in the garden at the end of the season to prevent the fungus from overwintering. Spraying the plants with a mixture of one part milk and nine parts water can help slow the spread of this disease.
Enjoy the Harvest
The best advice for harvesting summer squash is to pick early and often. Young fruits are the most tender; pick when the skin is glossy and soft enough to be easily pierced with your thumbnail. Harvest every two or three days, leaving a short piece of stem attached to the fruit to extend the storage life. If a few get away from you, harvest the over-mature fruits as soon as you notice them to keep you plants producing well. Simply add any "monster" squash or zucchini to your compost pile.
Q: The blossoms on my squash plants fall off and never form fruits. What's wrong?
A: Squash plants produce two different kinds of blossoms. Female flowers have what looks like a tiny squash at the base of the petals; male flowers are lacking this. Often just male flowers are formed at first, but once the female flowers appear, fruit should begin forming once these blossoms are pollinated. The male flowers will always drop without setting fruit. If the female flowers form but fail to set fruit, it may be that there are not enough pollinating insects around. This can be due to cold or rainy weather, in which case you can just wait for conditions to improve. You can also play bee yourself by picking a newly opened male flower, removing its petals, and dusting its pollen-carrying stamens against the pistil in the center of a newly opened female flower.
Article published on June 29, 2012.