So, you're thinking about growing Winter squash. You don't even have to explain why. Squash is easy to grow, healthy to eat and fun to use as an ornamental throughout the Fall and Winter seasons. Why wouldn't you want to grow Winter squash? Easy as it is to cultivate, here are the basics if you want to have a successful Winter squash crop:
Know The Difference: Make certain that you are getting Winter squash and not Summer squash. There is a difference and it matters. Winter squash takes longer to ripen. This makes it possible to grow it late into Fall. It has thicker skin than Summer squash, to protect the tender, inner flesh from the cold. And that thick skin results in a sweeter flavor. So, prepare for some delicious baked vegetable that could pass for dessert!
Seeds: Forget about purchasing starter plants, or sowing seeds indoors. Squash doesn't really like that transplanting business. For that reason, it is always best to sow a crop of Winter squash from your own seeds directly in the garden plot. There are so many interesting varieties with different shapes, colors and textures, why not get a seed collection that features multiple varieties like:
- Delicata: An heirloom variety with an outer skin of creamy shades of ivory to yellow, offset by dark green ribs. Inside is a sweet flesh of yellow/orange. Mature fruit of 12-14 inches is perfect to bake or set on the stoop with Fall decorations. Ready for harvest in about 80-100 days.
- Sweet Dumpling: Similar coloring as Delicata and reaches roughly the same height. However, instead of Delicata's elongated shape, this squash is a more traditional pumpkin shape. Ready for harvest in about 100 days.
- Table Queen Acorn: Although commonly found at your local grocer, perhaps year round, there is nothing like cultivating your own acorn shaped squash. This non-GMO variety features a rich, deep green outer skin that often has a splash of yellow. Under that skin is a bright, golden flesh. A single 6" fruit can weigh as much as 2 pounds. Ready for harvest in about 80 days.
- Table King Acorn: What sets the King apart from the Queen is the height of the plant and a splash of color that is orange, rather than yellow on the outer skin. Ready for harvest in about 80 days.
- Green Hubbard: Interesting oblong, teardrop shaped fruit with a bumpy, textured skin of dark green. Inner flesh is sweet and yellow. A single fruit can weigh as much as 15 pounds. That is definitely not snack size! Ready for harvest in about 105 days.
- Sweet Meat: Shades of sea-green nicely offset the dark greens of acorn squash and the vivid oranges and yellows of Fall pumpkins. The greenish-gray skin opens to reveal a deep orange flesh that is dry and tastes similar to a sweet potato. The flavor of this squash really lives up to its name. A 10-inch diameter fruit that weighs 10-20 pounds is typical of this Winter squash that is ready to harvest in about 105-115 days.
When To Sow: When there is no danger of frost and temperatures are still above 65 degrees Fahrenheit, Winter squash seeds can be sown directly into the garden. A tip for selecting garden site: squash crops should be rotated, allowing soil to rest for about 2 years after each harvest. Soil should be a fine, rich loam with good drainage. Choose an area that will receive plenty of sunlight. Work in compost and other organic material to enrich and loosen soil texture. To improve drainage, add some sand.
How To Sow: Place 1-2 seeds at a 1" depth about 36 inches apart. Mature plants will need plenty of room, often taking up as much as 6' of ground space. Instead of sowing in traditional garden rows, create mounds so the growing plants can spread outward, growing thick and bushy vines. Plants can also be trellised if space is at a premium in the urban garden. Keep soil evenly moist until seedlings appear.
Seedlings: Within 7-14 days seedlings will begin to appear. When seedlings have developed at least two sets of leaves, thin the weakest plant, keeping the healthiest and strongest.
Cultivation: As seedlings grow, weed the garden regularly. Squash has high nutrient demands and doesn't need the competition. Mulch is very helpful, suppressing weed growth while also providing another source of nutrients for the soil as the organic matter decomposes. Most squash varieties have a shallow root system so maintain soil moisture levels, watering well.
Watering Practices: Gardening style will affect watering practices. Generally, plants will need about 1-2 inches of water weekly. Squash needs a deep watering, delivering about 6-8 inches of water during a watering session in order to retain the 1-2 inches it requires. Mulching will mean less watering is required. Sandy soil or trellised plants may require more. When watering overhead, do so early in the morning to allow plenty of time for plants to dry so as to avoid moisture related diseases like mildew and fungus.
Pests & Disease: There may be fewer insects to worry about during cooler weather, but don't let your guard down. There are still a few pests and diseases to watch out for when growing Winter Squash.
- Bacterial Wilt: If vines show severe signs of wilting, Erwinia tracheiphila may be the culprit. It progresses rapidly so as soon as even a few vines show signs of wilting, take action. Most likely caused by the yellow and black striped cucumber beetle, the insect is actually spreading the bacteria. Because you want to attract pollinators, insecticide spray is not an option. Gardeners are left with hand-picking beetles or using beneficial insects like ladybugs or green lacewings that will consume the beetle's eggs. However, spot treatments with an organic insecticide on the underside of leaves may still be necessary.
- Powdery Mildew: If the surfaces of leaves turn a greyish color and seem to be coated with a powdery film, you are probably dealing with fungi like Sphaerotheca fuliginea or Erysiphe cichoracearum. Often the result of high humidity or poor air circulation through vines, this can show up late in the growing season when plants are full and heavy. You can use a commercial organic fungicide or make your own with a compost tea treated with baking soda.
- Blossom End Rot: If signs of rot appear on fruit before it fully develops, the weather may be too hot or your plants may have a calcium deficiency. Adding lime to the soil before watering will solve the calcium deficiency problem.
Harvesting: Use the fingernail test as fruit matures to see if it's ready. If a fingernail can easily pierce the skin, it's ready. Always harvest before a heavy frost when temperatures dip below 26 degrees Fahrenheit. Use pruning shears to separate the fruit from the plant at the stem. Leaving a couple of inches of stem on harvested fruit makes storage easier and more attractive decoration.
Storage: A well-ventilated, warm, dry indoor area is ideal for storage of Winter squash. It will last throughout Winter and into early Spring when stored like this. Long-term storage preferences are about 50 degrees Fahrenheit with about 60% humidity. Root cellars are perfect but a dark spot in a garage will do in a pinch. Steam and freeze or cube and can. However you store your Winter squash, be prepared to enjoy it all Winter long!
For more gardening tips, or to order your seeds today, contact your favorite gardening professional because the time to get your Winter squash seeds is now!