How to Sow and Grow Squash

Squash is one of those crops that, once you start growing it, you’ll wonder why you ever bought supermarket ones. With a vast array of shapes, sizes, and colours, heritage and heirloom varieties offer something far more exciting than the generic butternuts that dominate the shelves. Whether you fancy a sprawling pumpkin patch or compact bush varieties for small spaces, there’s a squash for you!

Sowing Squash Seeds

Squash is a warm-weather crop, so timing is everything. In cooler climates like we get here in the UK, it’s best to start seeds indoors in April or early May to give them a head start. Use deep pots (squash hate having their roots disturbed) and a free-draining seed compost. Sow seeds on their side about an inch deep – this helps prevent rotting. Keep them warm (around 18-21°C) and they should germinate within a week.

Once they have their first true leaves, start hardening them off by gradually exposing them to outdoor conditions over a week or two before planting out.

Planting Out Squash

By late May or early June, when all risk of frost has passed, your squash should be ready to go outside. These plants are hungry and thirsty, so give them the richest soil you can manage. Dig in plenty of well-rotted manure or compost before planting and space them generously – at least 90cm apart for trailing varieties and 60cm for bush types.

Squash love warmth, so a sunny, sheltered spot is ideal. If you’re short on space, heirloom climbing varieties like ‘Tromboncino’ can be grown up a trellis. Not only does this save space, but it also keeps the fruits off the ground and away from slugs!

Caring for Your Squash Plants

Water deeply and regularly, especially during dry spells, but try to keep the leaves dry to avoid mildew. A mulch of straw or grass clippings can help retain moisture and suppress weeds.

Feeding is crucial – a weekly liquid feed high in potassium (like comfrey tea) will encourage strong growth and plenty of fruit. If you’re growing large heritage pumpkins, pinch out the growing tips once they have set a few fruits to direct energy into ripening them.

Harvesting & Storing Squash

Summer squash (like courgettes) are best picked young for the best texture and flavour, while winter squash and pumpkins need to ripen fully on the vine. Leave them until the skins have hardened and the stems start to dry out, then cut them with a good few inches of stem attached.

For storage, cure winter squash by leaving them in a warm, dry spot for a couple of weeks before moving them to a cool, dark place. Properly cured squash can last for months, providing delicious homegrown goodness well into winter.

Why Grow Heirloom & Heritage Squash?

Beyond the thrill of growing something unique, heirloom and heritage varieties often have superior flavour, resilience, and fascinating histories. 

Whether you’re growing for food, fun, or both, squash is a must-have in any veg garden. Pick a few varieties, experiment with different growing techniques, and prepare for a bumper harvest of weird and wonderful fruits!