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how to grow butternut squash

How to grow butternut squash

Grown through summer for harvest in autumn, easy to grow butternut squash are a valuable crop for use through the winter months. The number of butternut squash recipes available on the net is a clear indication of their versatility and popularity in the kitchen. Butternut squash should store for up to 3 months in a cool, frost-free shed, packed in cardboard boxes in straw.

butternut squash butterbush

Butternut squash varieties to try

  • British-bred Harrier Butternut squash is the most common and reliable variety for growing in the UK. The plants each produce 4 or 5 long,pear-shaped fruits.

  • Butterbush butternut squash is a better option where space is a consideration. The compact bushy plants spread little over three feet, making it the best butternut squash varieties for container growing and small gardens.

  • For something different, try the green and orange striped Barbara butternut squash. This decorative variety also benefits from a small seed cavity and a fuller shape, producing more flesh per fruit.

Choosing a site

Growing butternut squash at home or on the allotment is easy, given a sunny spot and a rich, free-draining soil. Plenty of compost and horse manure should be added to the soil when preparing the planting area. If you don’t want to turn over the whole plot, you can prepare individual planting pockets, 45cm (18") wide and deep, spaced 1m (3ft) apart.

sowing butternut squash

How to sow butternut squash seeds

Being large and flat, butternut squash seeds are easy to work with, and make good sowing projects for children.

For the earliest crops, sow indoors from late April. Sow individually in small pots filled with multi-purpose compost. Yoghurt pots are a good alternative. Sow the seeds about 1 inch deep on their sides. Place pots in a propagator or clear plastic bag and set on a warm windowsill until seeds germinate. At this point, remove covers but keep in the warmth.

Young butternut squash plants are easy to handle thanks to large foliage and thick stems, but treat them delicately as you transfer them to the garden or allotment. Harden them off for a week or so, after all danger of frosts and plant out.

Alternatively, sow outdoors in May in soil that has been pre-warmed with a cloche. Sow two seeds per station and thin to the strongest seedling if both seeds germinate.

How to grow butternut squash in pots

Trailing varieties are best left for the vegetable patch. For success in pots, choose compact bush varieties such as Barbara. Use the largest pot you can, aiming for a minimum of 45cm (18in) diameter and just as deep. Two plants should perform well in a grow bag. Set in a spot and water regularly to prevent compost from drying out. Do away with frequent feeding through the season by adding incredicrop® to your compost at planting time. With 7 months coverage it will last the life of these long season plants.

butternut squash varieties

Butternut squash growing tips

  • As plants begin to sprawl and grow into each other it can be hard to locate the centre of the plant for watering. Set a cane by each plant when planting out to act as a marker later in the season.

  • Double up on space by growing butternut squash around the base of sweetcorn plants.

  • No space left on the veg patch? You can even try growing butternut squash directly on the compost heap!


Kris Collins

Written by: Kris Collins

Kris Collins works as Thompson & Morgan’s communications officer, making sure customers new and old are kept up to date on the latest plant developments and company news via a wide range of media sources. He trained in London’s Royal Parks and has spent more than a decade writing for UK gardening publications before joining the team at Thompson & Morgan.