How To Grow Butternut Squash (Winter Squash)

How To Grow Butternut Squash (Winter Squash)

Homegrown butternut winter squashSquash plants are closely related to cucumbers, courgettes and marrows, and are a member of the same family, curcurbit. Squash plants come in a variety of shapes and sizes, and include butternut squash, spaghetti squash, and pumpkins.

Squashes generally have a rich, orange flesh, but their outer skins can range from pale cream to darkest green. Squashes can be subdivided into two categories: summer squash and winter squash. Winter squash are ready to harvest from mid-late autumn and are ideal for storing to use over the winter months.

All squash plants are grown in the same way, requiring a lot of space and nutrients. Set aside a generous portion of your plot to grow them in and add plenty of organic matter, such as homemade compost or well-rotted manure. This will provide them with sufficient nutrients to see them through their long growing season.

Sowing winter squash seeds in potsSowing Squash

Pumpkins and winter squashes are sown in late April or early May, under protection, in a greenhouse, conservatory or window sill indoors. These plants cannot tolerate frost. The seeds can be sown directly where they are to grow outdoors in the second half of May, but the four or five weeks indoors gives them a head-start. Sow one seed, on its edge, in a 12cm pot to avoid potting on. Be careful not to over-water at sowing as wet, airless compost can cause the seed to rot. Allow the compost to dry a little before watering, but do not delay watering.

Planting Out Harden off the seedlings towards the end of May or early June and plant outside after a few days of warm weather. The planting site can have been prepared earlier, digging in lots of well-rotted compost or manure. Set the plant on a slight mound with the top of the compost rootball about two centimetres out of the soil. Make a little moat around the mound, about 25 centimetres from the plant to allow for watering later. If the plant is a bit floppy, a light cane can be used to secure it against wind damage.

Immature butternut winter squashGrowing Tips
When the plant’s main shoots have grown to 60cm long, trim them back so the plant’s energy is concentrated on producing flowers and fruit, rather than masses of foliage.
Encourage pollinators, such as bees to the area by planting native wildflowers (foxgloves, sunflowers and echinacea) near your vegetable plot. When the bees gather nectar and pollen from the wildflowers, they will also stop by and pollinate your vegetable blooms, which lead to more fruit setting, increasing your yield

Soil-borne pests or fungal diseases can damage the tender fruits, so support them by lifting them off the ground, using bricks, tiles, or even polythene.

Harvesting winter butternut squash plantsHarvesting Squashes
Harvest summer squashes when the fruits are still small, ensuring they are more flavoursome. Use a clean, sharp pair of scissors or secateurs and snip the stem, avoiding wounding it, which can let in infection.
For pumpkins and winter squashes intended for storing over winter, allow the fruit to fully mature on the plant and then harvest it when the foliage has died down, making sure you have harvested them before the first frost. Butternut squash tends to have a long shelf life so stores very well overwinter.