Originally appeared at National Gardening Bureau
From seed to harvest, learn the secrets to growing a bumper crop of delicious summer and winter squash.
Summer and winter squash are crops that offer huge payback. They’re both easy to grow, fairly low maintenance, and there are so many delicious varieties to try. Summer squash plants yield tender fruits all summer long while winter squash mature at the end of the season and can be stored for months of winter meals.
Written by Niki Jabbour
Squash are heat-loving vegetables and shouldn’t be planted until after the last frost date in spring. They can be direct-seeded or you can give the plants a head start by sowing the seeds indoors three to four weeks before you harden them off and move them to the garden.
Squash need a site that offers at least eight hours of full sun, rich soil, and consistent moisture to grow and produce well.
There are four main ways I grow squash in my vegetable garden:
- I grow both winter and summer squash in seasoned straw bales at the back of my garden. Squash love a rich growing medium and the composting straw bales provide everything squash plants need to reach maximum production.
- After the growing season has come to an end I leave the half composted straw bales at the back of my garden. The following spring I layer that partially rotted straw with compost or aged manure to create soil-free beds for my squash and pumpkin plants.
- Finally, I tuck a few squash seedlings in my compost pile. I use a bin made from pallets so it’s easy to plant a couple of squash plants halfway down where the materials have partially composted. The plants thrive in this organic mixture and happily climb on and around the compost pile.
Before planting squash in my garden beds, it’s essential to prep the soil. Squash love rich soil and so I add three to four inches of compost or aged manure. I also add a slow-release organic vegetable fertilizer to the site at planting time.
When planting summer squash in my raised beds, I sow the seeds one inch deep and a foot apart, eventually thinning to three feet apart.
For winter squash, sow the seeds one inch deep in rows or hills. Plant three seeds per hill, eventually thinning to the strongest plant. In rows, space the seeds a foot apart, thinning to three feet apart. Rows and hills should be 4 to 6 feet apart, depending on the variety.
Both summer and winter squash plants have high fertility demands and need consistent moisture. I fertilize the plants every three to four weeks with liquid organic fish food. I also water deeply each week if there has been no rain.
There are several diseases and pests that can affects squash so I keep a close eye on my plants and take action when necessary.
Here are three issues to watch out for:
- Powdery mildew – Powdery mildew is a fungal disease that shows up as a whitish-gray coating on the leaf surface. Leaves eventually turn brown and die. Overall yield can be affected. To minimize the risk of powdery mildew, when irrigating water the soil, not the leaves. Also, be sure not to overcrowd when planting. Good air circulation between plants helps the foliage dry off quickly after rain or irrigation.
- Squash bugs – These pesky bugs suck the sap from the leaves of your squash plants causing yellow spots that eventually turn brown. Squash bug adults are large, flat dark gray insects and their nymphs are small and light gray. Practice crop rotation and use row covers as soon as squash seeds or seedlings are planted to prevent a squash bug infestation. Remove covers once the plants begin to flower.
- Squash vine borers – The adult form of the squash vine borer is a clearwing moth, but it’s the cream-colored larvae that do the damage. The adults lay eggs at the base of squash plants. As the eggs hatch, the larvae bore into the stems to feed. This blocks the flow of water which causes the first noticeable symptom: wilting foliage. If you see wilted leaves, look closely at the base of your plants for small holes and telltale frass (poop). To prevent this destructive pest, plant resistant varieties. Certain types of squash, like butternut, are not as susceptible to squash vine borers. It also pays to wait to plant. If you wait a few extra weeks to sow seeds or plant seedlings, early emerging adults will need to go somewhere else to lay their eggs.
How to pollinate squash flowers:
You may be wondering WHY you’d want to pollinate your squash flowers. Isn’t that a job for the bees? And yes, bees certainly do most of the pollination of my squash plants, as well as related cucumbers and melons, but I like to give the bees a helping hand to ensure all my female flowers are pollinated.
It’s important to understand that squash plants have separate male and female flowers on each plant. For fruit to form, pollen from a male flower must be transferred to a female flower. It’s easy to tell them apart. The male flowers have a straight stem beneath the bloom while female flowers have a baby squash under the bloom. If pollination doesn’t occur, the tiny fruit at the bottom of the female flower will rot and fall off.
Typically, the first flowers to appear on squash plants are males. This is totally normal and soon you’ll see female flowers. Once you have both male and female flowers, pollination should happen with the help of bees, but problems can occur when there are too few bees, or the weather is too hot, cold, or wet and affects pollen quality.
I spend a lot of time in my garden, and when I spot newly opened female squash flowers, I hand pollinate to boost my chances of a fruit forming.
Here are two simple steps to hand pollinating squash:
- To hand pollinate you can use a male flower, a Q-tip, or a clean small bristle paintbrush. I usually use a male flower, picking a fresh stem, and removing the petals.
- Press the anther of the male flower to the stigma of female flowers. One male can pollinate several female flowers. Or, use a Q-tip or paintbrush to transfer pollen.
Great squash to grow in your garden:
Oh baby, this is a variety that every winter squash lover should grow! The plants are very compact, just two to three feet long which makes them ideal for small spaces, raised beds, or containers. Expect eight to nine personal-sized squash per plant with each growing up to seven inches long. They’ll weigh a quarter to a half pound and we love to steam or bake them.
Sunshine lights up the garden with glowing orange fruits that are as delicious as they are beautiful. Each compact vine yields a good crop of three to four-pound squash that have a round, flattened shape. The flesh is also bright orange and has a sweet nutty flavor and creamy texture. The fruits can be stored for months so you can enjoy them well into winter.
Unlike most cultivars of spaghetti squash which have tan-colored rinds, Sugaretti has eye-catching striped fruits that taste as good as they look! Each medium-sized squash grows up to 10 inches long and has a too-good-to-be-true sweet, nutty flavor. The plants themselves are quite compact, only growing a few feet across and they’re also resistant to powdery mildew. Bake the beautiful fruits and use the flesh as a pasta substitute.
There are so many reasons to love Butterscotch. First, the adorable one to two-pound fruits are perfect for two people, or one with leftovers. Also, the sweet flesh is incredibly rich and smooth and is ready to enjoy right from the garden – no need to cure the fruits first. Each plant yields three to four fruits and the short vines are resistant to powdery mildew.
For over two decades, vegetable gardeners have been growing this incredibly productive summer squash which produces fruits all summer long. It’s early to crop with the first fruits ready to pick just 50 days from seeding. Harvest when the round fruits are two to three inches across or allow them to get to five inches across if you wish to bake and stuff them.
The beautiful dark and light green mottled exterior of this zucchini squash really sets it off in your garden. The flavor is quite mild and sweet, with no trace of bitterness. The compact plant starts producing early and continues 3-4 weeks later than most zucchini. Delicious in summer recipes!
Delightful scalloped (pattypan) squash the size of teacups has the perfect combination of firm and tender texture, not to mention a sweet, mild taste! The immature 2-3 inch squash can be picked and cooked whole or grown larger and cooked with other tasty vegetables. Sunburst is a buttery-flavored squash making it perfect for a stir fry dinner.
The perfect compliment to Sunburst squash in any recipe is Peter Pan hybrid scallop squash. These squash are light green and have a firm texture. These plants are compact bush type so will do well in your container. A vigorous producing fruit earlier than the standard.
This post is provided as an education/inspirational service of All-America Selections.