How to Grow Squash

Squash is one of my favorite vegetables to grow in the garden. I love their big yellow blooms and the amount of food they produce. Whether you prefer summer squash like zucchini or winter squash such as butternut, you will find many uses in the kitchen. Follow this guide to learn how to grow squash successfully.

How to Grow Squash: Choosing the Right Variety

Squash comes in many varieties, broadly categorized into summer and winter squash. Choose your variety based on your space and culinary preferences. Refer to the seed packet for the growth habit. Some squash varieties grow in a bush-type habit, while others are vining which requires more space or trellising.

Summer Squash: Includes zucchini, yellow squash, and pattypan. These are harvested while immature and tender.
Winter Squash: Includes butternut, acorn, and spaghetti squash. These are harvested when mature and can be stored for months.

How to Grow Squash: Planting

Timing: Squash can be started indoors and transplanted or directly sown in the garden.
- Starting Indoors: Start seeds indoors 2-4 weeks before the last frost. Sow seeds 1/2 inch deep in the seed starting mix. Transplant seedlings outdoors when they have 2-3 sets of true leaves and the soil is warm. Refer to my article about seed starting: How to Grow Plants from Seed
- Direct Sowing: Plant seeds directly in the garden after the danger of frost has passed and the soil temperature is at least 60°F (15°C). Sow seeds 1/2 inch to 1 inch deep and 2-3 inches apart. Thin seedlings to the recommended spacing on the seed packet.
Location: Squash needs full sun, so choose a location that gets at least 6-8 hours of sunlight daily. The soil should be well-draining and rich in organic matter. Squash plants get big, especially the vining varieties, so choose a site with plenty of room.
Soil Preparation: Squash thrives in fertile soil. Amend the soil with compost or well-rotted manure to improve fertility and drainage.
Planting: Squash plants can be quite large, so ensure ample space. For summer squash, space plants about 18-24 inches apart. For winter squash, which spreads more, space them 24-36 inches apart. Squash grows well next to corn and beans. Avoid planting near potatoes or other members of the nightshade family. For a continuous harvest, consider planting squash in succession, especially summer varieties.

How to Grow Squash: Plant Care

Watering: Squash needs consistent moisture, especially during flowering and fruit development. Water plants deeply once a week, or more often in very hot weather. Avoid wetting the leaves to reduce the risk of fungal diseases.
Fertilizing: Squash is a heavy feeder. Apply a balanced fertilizer or compost at planting and again when the plants begin to flower. Avoid high-nitrogen fertilizers, which can encourage leaf growth at the expense of fruit.
Supporting: For squash varieties that have bush-like habits, you might consider staking them upright to allow for more plants in less space. For vining varieties, you can either let them sprawl across the ground or train them up a trellis to preserve space. I use welded wire fencing to trellis my vining squash. Once the squash gets large and heavy, I use my kids’ old dance tights to support their weight by creating a sling tied to the trellis.

How to Grow Squash: Pollination

Squash plants produce separate male and female flowers. Pollination is typically done by bees, but you can assist by gently transferring pollen from male to female flowers with a small brush or Q-Tip. For best results, hand-pollinate in the morning when the flowers are open.

Male Flowers: These are produced in abundance and have long, thin stems.
Female Flowers: These have a small, swollen ovary at the base of the flower.

How to Grow Squash: Pest and Disease Management

Pests: Squash bugs, cucumber beetles, and squash vine borers are common pests. Monitor your plants regularly and use organic insecticides or hand-picking to manage infestations. I prefer the hand-picking method, so I keep a bucket of water in the garden to toss the bugs into. I also look for squash bug eggs on the underside of the leaves and will remove those by hand.
Diseases: Watch for powdery mildew, downy mildew, and blossom end rot. Ensure good air circulation, avoid overhead watering, and remove affected plant parts. Crop rotation and choosing disease-resistant varieties can help prevent many issues.

How to Grow Squash: Harvesting and Storage

Summer Squash: Harvest when fruits are young and tender, typically when they are 10 inches long. If you let the squash get too big, the seeds will fully develop and the inside will have an undesirable sponge-like texture. Regular harvesting encourages more fruit production. Harvest using clean pruning shears or firmly hold and twist where the fruit meets the stem. Store on your kitchen counter if using within the next day or two, otherwise store in your refrigerator for 1-2 weeks. For long term storage for recipes like zucchini bread, shred the squash and place in the wells of a muffin pan. Place the muffin pan in the freezer until the shredded zucchini is frozen into blocks, then put the zucchini blocks into a freezer bag and store the bag in the freezer.

Winter Squash: Harvest when the skin is hard and the stem is dry. You can test the skin by pushing your fingernail against the skin. If it leaves a mark, the skin is still soft. Another indicator that the squash is ready to harvest is when the tendril closest to the squash has completely dried. Cut the fruit from the vine, leaving a few inches of stem attached. Store in a cool, dry place for several months.

Final Thoughts

There’s something special about going out to your garden and watching the squash get bigger day by day. Growing your own squash not only brings delicious and versatile meals to your kitchen but also adds vibrancy to your garden with beautiful squash blossoms. With a little bit of care, you will be rewarded with a bountiful harvest of tender summer squash and hearty winter squash.