Acorn Squash in Zone 10B — Florida

Acorn squash is a fantastic addition to your Florida garden. Its nutty, slightly sweet flavor makes it incredibly versatile in the kitchen, perfect for roasting, stuffing, or pureeing into soups. Plus, there's a real satisfaction in harvesting your own winter squash right here in our subtropical climate.

Our Florida gardening calendar is different, and you might think squash is a challenge with our humidity and potential for pests. But with careful timing, planting in fall and harvesting in winter, you can absolutely grow beautiful acorn squash during our prime growing season. We have a 360-day growing season, so there's plenty of opportunity.

Starting acorn squash indoors is possible, but direct sowing is generally preferred, especially here in Florida. If you want a head start, begin late December through mid January, about three weeks before you'd like to transplant. Use seed trays with a good seed-starting mix, provide warmth (a heat mat helps), and ensure adequate light with grow lights.

Be sure to water from the bottom to prevent damping off, which can be a problem in our humid climate. Remember our reversed spring, though – don't get fooled by an early warm spell into starting too soon!

Transplant your seedlings outdoors mid January through mid February. Before transplanting, harden off your seedlings by gradually exposing them to outdoor conditions for about a week. This is important to prevent shock. Space your plants 36-48 inches apart.

Keep an eye on the weather during this time. While we don't typically get hard freezes, unexpected cool snaps can still occur. Protect your young plants with row covers if temperatures dip unexpectedly.

Direct sowing is the recommended method for acorn squash in Florida. Sow seeds mid January through late September, giving the vines plenty of time to mature before any potential frosts. Soil temperatures should be at least 60°F for optimal germination. Prepare your planting area by amending the sandy soil with plenty of compost and well-rotted manure.

Plant seeds 1 inch deep and space them 36-48 inches apart. Winter squash needs a long growing season, but direct sowing works well in our extended warm periods.

Acorn squash needs consistent moisture to thrive, but overwatering can be a problem, especially with our very-high humidity. During our drier fall and winter months, aim to water deeply once or twice a week, providing about 1-2 inches of water each time. Use the "finger test"—stick your finger about 2 inches into the soil; if it feels dry, it's time to water.

During our wet-summer, you may only need to supplement watering during dry spells. Always water at the base of the plant to avoid wetting the foliage, which can encourage fungal diseases in our humid conditions. Signs of underwatering include wilting leaves, while yellowing leaves can indicate overwatering.

A layer of mulch around the base of your plants will help retain moisture and suppress weeds. Pine straw or wood chips work well in our climate.

You can expect your first acorn squash harvest from early April through late December here in Zone 10B. The squash are ready to harvest when the skin is a dark green color with an orange spot where it has been resting on the ground. The shell should be hard, and the stem should be dry and starting to crack.

Use a sharp knife or pruners to cut the squash from the vine, leaving a few inches of stem attached. This helps prevent rot. Acorn squash doesn't ripen off the vine, so be sure it's fully mature before harvesting.

As late December approaches and our first frost is on the horizon, harvest any remaining squash, even if they're not quite fully ripe. Smaller, immature squash may not store as well, but they're still edible.

Acorn squash can face several challenges in Florida, including squash vine borers, powdery mildew, squash bugs, and cucumber beetles.

Squash Vine Borer

• What it looks like: Wilting vines that suddenly collapse, often with small holes near the base of the stem and sawdust-like frass (larval excrement).
• What causes it: Moth larvae that bore into the stems and feed on the plant tissue. They thrive in our warm climate.
• How to fix/prevent it: Wrap the base of the stems with aluminum foil or pantyhose to prevent the moths from laying eggs. Inspect stems regularly and remove any larvae you find. You can also try injecting Bacillus thuringiensis (Bt) into the stems to kill the borers.

Powdery Mildew

• What it looks like: White or grayish powdery coating on leaves, stems, and sometimes fruit. Leaves curl, yellow, and die. Reduces plant vigor.
• What causes it: Various fungi that thrive in warm days, cool nights, and moderate humidity. Dry leaf surfaces actually favor it (unlike most fungi).
• How to fix/prevent it: Improve air circulation through spacing and pruning. Remove affected leaves. Neem oil or potassium bicarbonate sprays help. Milk spray (1 part milk to 9 parts water) is surprisingly effective. Plant resistant varieties.

Squash Bugs

• What it looks like: Gray-brown shield-shaped bugs on leaf undersides. Bronze egg clusters on leaves. Wilting leaves that turn brown and crispy.
• What causes it: Sap-sucking insects that inject toxin while feeding. Adults overwinter in garden debris and emerge in spring.
• How to fix/prevent it: Hand-pick adults and crush egg clusters. Board traps (adults hide under boards at night — flip and destroy in morning). Neem oil spray. Remove plant debris in fall. Companion plant with nasturtiums.

Cucumber Beetles

• What it looks like: Small yellow-green beetles with black spots or stripes on leaves and flowers. Leaves have small holes. Plants may wilt suddenly from bacterial wilt transmitted by beetles.
• What causes it: Adult beetles feed on leaves and flowers and transmit bacterial wilt disease. Larvae feed on roots.
• How to fix/prevent it: Row covers until flowering (remove for pollination). Hand-pick adults. Yellow sticky traps. Neem oil or pyrethrin spray. Kaolin clay coating. Interplant with radishes or nasturtiums as trap crops.

Florida Specific Challenges: The combination of hot heat, very-high humidity, and wet-summer rainfall creates a perfect environment for fungal diseases and pests. Regular monitoring and proactive measures are crucial for success. Consider choosing nematode-resistant varieties, as nematodes can be a real issue in our sandy soil.

Good companions for acorn squash in Florida include corn, green beans, radishes, and marigolds. Corn provides a natural trellis for the squash vines. Green beans fix nitrogen in the soil, benefiting the squash. Radishes deter pests like squash vine borers. Marigolds repel nematodes and other harmful insects.

Avoid planting acorn squash near potatoes or brassicas (cabbage, broccoli, cauliflower). Potatoes compete for the same nutrients, and brassicas can attract pests that will also attack your squash.