Acorn Squash in Zone 9B — Florida

Acorn squash is a fantastic addition to the Florida garden. Its nutty, slightly sweet flavor is perfect for roasting, stuffing, or adding to soups and stews. Plus, there's a real satisfaction in harvesting your own winter squash when everyone else is just starting to think about fall, especially with our reversed seasons down here.

Sure, we've got our share of gardening challenges in Florida, like humidity and nematodes, but with a little planning and the right timing, you can absolutely grow beautiful acorn squash right here in Zone 9B. Our long 344-day growing season gives you plenty of opportunity to get a great harvest.

While acorn squash thrives when direct-sown, starting seeds indoors gives you a head start, especially if you're aiming for an earlier harvest. This is most useful for a spring planting. Start your seeds indoors in early to late January, about three weeks before you intend to transplant them outside.

Use seed trays or small pots filled with a good quality seed-starting mix. Keep them warm and provide plenty of light, either from a sunny window or a grow light. An easy way to keep the soil evenly moist is to water from the bottom by placing the tray in a shallow dish of water. Remember, our spring here is reversed, so getting a jump start can be beneficial.

Transplant your acorn squash seedlings outdoors in early February through early March, once they have a few sets of true leaves. Before planting, harden them off by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the Florida sunshine and temperatures, preventing transplant shock.

Space your plants 36-48 inches apart to allow for plenty of room to grow. Keep an eye on the weather; we can still get some cool snaps during this time, so be prepared to cover your seedlings if temperatures dip unexpectedly.

Direct sowing is the preferred method for growing acorn squash in Florida. The soil warmth from late spring through summer makes this method very successful. Sow seeds directly into the ground from late January through late September, ensuring the soil temperature is at least 60°F.

Prepare your planting area by amending the soil with compost or well-rotted manure. Plant seeds about an inch deep, spacing them 36-48 inches apart. Water well after planting and keep the soil consistently moist until the seedlings emerge. Even though winter squash needs a long growing season, direct sowing works wonderfully in our extended warm climate.

Acorn squash needs consistent moisture, especially during its active growing period. Aim for moderate watering throughout the growing season but reduce the frequency slightly as the fruits mature to prevent rot. This is especially important in our humid Florida climate.

During the hotter months, particularly in summer, you'll likely need to water deeply two to three times a week, providing about 1-2 inches of water each time. Use the "finger test" – stick your finger into the soil about 2 inches deep. If it feels dry, it's time to water. Water at the base of the plant to avoid wetting the leaves, which can encourage fungal diseases in our humid environment.

Signs of underwatering include wilting leaves and stunted growth. Overwatering can lead to yellowing leaves and root rot, which is a common problem in Florida's heavy summer rains. Mulching around your plants with straw or pine needles helps retain moisture, suppress weeds, and regulate soil temperature, which is beneficial in our sandy soils.

You can expect your first acorn squash harvest in late April through late December, depending on when you planted. Acorn squash is ready to harvest when the skin is dark green with a noticeable orange spot where it rested on the ground. The shell should be hard, and the stem should be dry and tough.

To harvest, use a sharp knife or pruners to cut the squash from the vine, leaving a 2-3 inch stem attached. This helps prolong its storage life. Avoid damaging the squash during harvest, as any cuts or bruises can lead to rot.

As our first frost approaches in late December, harvest any remaining squash, even if they aren't fully mature. While they won't ripen off the vine, you can still use them in cooking, though the flavor might be milder.

Here are some common problems you might encounter growing acorn squash in Florida:

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.
• What causes it: Larvae of the squash vine borer moth burrow into the stems, feeding on the plant tissue. They thrive in warm weather.
• How to fix/prevent it: Wrap stems with foil or netting to prevent moths from laying eggs. Inject Bacillus thuringiensis (Bt) into the stem near the entry point to kill larvae. Monitor plants regularly and remove any infested vines.

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: Our hot, humid summers and sandy soil can exacerbate these problems. High humidity encourages fungal diseases like powdery mildew, and our sandy soil requires careful watering and soil amendment to keep plants healthy and resistant to pests and diseases. Nematodes are a constant threat, so choose nematode-resistant varieties if possible.

Companion planting can really help your acorn squash thrive in the Florida garden. Corn provides a natural trellis for the squash vines, and beans fix nitrogen in the soil, benefiting both plants. Radishes help deter squash vine borers, and marigolds repel nematodes and other pests.

Avoid planting acorn squash near potatoes or brassicas like cabbage and broccoli. Potatoes compete for nutrients, and brassicas attract pests that can also affect your squash. Keeping these plants separate will help ensure a healthier and more productive squash crop in your Florida garden.