Yellow Squash in Zone 8B — Texas

Yellow squash is a winner in the Texas garden. It's prolific, delicious sautéed, grilled, or baked, and you can even eat the blossoms! Plus, there's something deeply satisfying about harvesting armfuls of squash you grew yourself, especially with our long growing season that allows for multiple harvests.

We all know Texas weather is unpredictable, and growing anything here comes with its own set of challenges, from extreme heat to the occasional late freeze. But with a 273-day growing season, smart timing, and a little planning, you can definitely enjoy a bountiful yellow squash harvest.

Starting yellow squash indoors gives you a head start, especially if we have an early warm spell. Begin indoors from mid-February through early March, about three weeks before you plan to transplant. Use seed trays or small pots filled with a good seed-starting mix.

Keep the soil consistently moist, and bottom watering is a great way to avoid damping off. Provide warmth (a heat mat helps) and plenty of light, either from a sunny window or a grow light. Remember, spring in Texas can arrive early, so keep an eye on the forecast!

Transplant your yellow squash seedlings outdoors from mid-March through late April. Before transplanting, harden them off by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the Texas sun and wind.

Space plants 24-36 inches apart to give them plenty of room to grow. Keep an eye on the forecast – a late freeze can still happen. If frost threatens, cover your seedlings with row covers or blankets.

Direct sowing is the easiest and most common way to grow yellow squash in Texas. You can direct sow from early March through late September, giving you plenty of time for multiple crops. Yellow squash grows quickly from seed, so you'll be harvesting in no time!

Choose a spot with full sun (at least 6-8 hours a day) and well-drained soil. Amend the soil with compost before planting. Plant seeds about 1 inch deep and space them 24-36 inches apart. Keep the soil consistently moist, especially during germination.

Yellow squash needs consistent watering, especially during our hot Texas summers. They are *not* drought-tolerant, so don't let them dry out. The key is deep, infrequent watering rather than shallow, frequent sprinkles.

During the cooler spring and fall months, water deeply about once a week, providing about 1-2 inches of water. In the peak of summer, you may need to water every other day, or even daily, depending on rainfall and soil drainage. Stick your finger about 2 inches into the soil – if it feels dry, it's time to water. Always water at the base of the plant to avoid wetting the leaves, which can encourage fungal diseases with our variable humidity.

Signs of underwatering include wilting leaves and stunted growth. Overwatering can lead to root rot, so watch for yellowing leaves and a mushy stem base. A good layer of mulch around your squash plants helps retain moisture and suppress weeds, which is especially helpful during our unpredictable rainfall patterns.

You can expect your first yellow squash harvest from late April through late November, about 50 days after planting. The best time to harvest is when the squash is 6-8 inches long and the skin is still tender enough to dent with your fingernail. Overgrown squash gets tough and seedy.

Use a sharp knife or pruners to cut the squash from the vine, leaving a short stem attached. This helps prevent rot. Yellow squash is a continuous harvest crop, meaning it will keep producing as long as you keep picking the ripe ones.

As our first frost approaches in late November, harvest any remaining squash, even if they're a little small. While they won't ripen off the vine, you can still use them in soups and stews.

Yellow squash is susceptible to a few common problems in Texas gardens. Here's how to identify and address them:

Squash Vine Borer

• What it looks like: Wilting vines that suddenly collapse, often with small holes near the base of the plant and sawdust-like frass.
• What causes it: Moth larvae that tunnel into the stems and feed on the plant's tissue.
• How to fix/prevent it: Wrap the base of the stems with foil or netting to prevent moths from laying eggs. If you see signs of borers, you can try to surgically remove them by slitting the stem and extracting the larvae. Injecting *Bacillus thuringiensis* (Bt) into the stem can also help.

Powdery Mildew

• What it looks like: White or grayish powdery coating on leaves, stems, and sometimes fruit. Leaves curl, yellow, and die.
• What causes it: Various fungi that thrive in warm days, cool nights, and moderate humidity. Dry leaf surfaces actually favor it.
• 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.

Blossom End Rot

• What it looks like: Sunken, dark brown or black leathery patch on the bottom (blossom end) of fruit. Often affects first fruits of the season.
• What causes it: Calcium deficiency caused by inconsistent watering. Not a disease — it's a nutrient uptake problem triggered by drought/flood cycles.
• How to fix/prevent it: Water consistently (the single most effective fix). Mulch heavily to maintain even soil moisture. Don't over-fertilize with nitrogen. Calcium sprays help marginally. Remove affected fruit.

Texas Specific Challenges: The hot-to-extreme Texas heat can stress yellow squash plants, making them more susceptible to pests and diseases. Variable humidity and unpredictable rainfall can also contribute to fungal problems and blossom end rot. Consistent watering and good air circulation are key to keeping your plants healthy. And don't forget to watch out for fire ants when you're working in the garden!

Companion planting can help your yellow squash thrive. Corn provides partial shade, which can be beneficial during the hottest part of the Texas summer. Beans fix nitrogen in the soil, which benefits squash. Radishes deter squash vine borers, and marigolds repel nematodes and other pests.

Avoid planting yellow squash near potatoes, which compete for nutrients. Also, avoid planting near brassicas (like cabbage and broccoli), as they attract similar pests. Planting strategically can help you create a healthier and more productive garden, especially in our challenging Texas climate.