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Growing Butternut Squash UK

One of the most popular squashes to grow is butternut squash. It’s scientific name is Cucurbita Moschata. The bulbous, pear-shaped fruits, which have thick, sweet orange flesh and thin skin, are available to harvest in the autumn. This makes them simple to prepare and ideal for roasting or adding to soups and risottos. Butternut squash is also a fantastic vegetable for your health, as it is low in carbs and high in vitamins.

In the United Kingdom, British-bred harrier butternut squash is the most frequent and reliable kind to grow. Each plant produces four or five long, pear-shaped fruits. When space is an issue, butterbush butternut squash is a better choice. It’s one of the finest butternut squash kinds for container cultivation and tiny gardens, thanks to its compact bushy vines that extend just over three feet. Try the green and orange striped Barbara butternut squash for something unusual. This ornamental variety has a smaller seed chamber and a larger form, resulting in more flesh per fruit.

Method of Planting

In the UK the butternut squashes are usually sown from April to June. Beginning early April, sow butternut squash seed in 7cm pots of peat-free, multi-purpose compost. When seedlings are grown enough to handle, transplant them into larger pots, and then plant them outside in healthy soil once the risk of frost has gone, which should be around late May. Slugs and snails may wreak havoc on young plants, so make sure to keep your plants safe from them. Butternut squashes are hungry plants, so water them regularly and begin feeding them weekly once they begin to bloom. Remove any leaves that are covering the immature squashes to allow them to ripen properly, and consider elevating the fruits off the ground onto bricks or straw to allow them to ripen fully.

Planting indoors or outdoors

It is easy to grow butternut squash from seeds.  Start spreading two seeds per container inside in early April. After the last frosts, thin to one seedling and harden off outside before planting out in late May into well-prepared beds.

In late May and early June, butternut squash can also be sown directly into the soil, outside, where they will thrive. A good amount of well-rotted organic materials should be dug into the soil if planted outside.

Soil Preparation

 The planting area must be prepared in advance by digging in a large amount of well-rotted compost or manure. Set the plant on a slight mound, with the compost rootball’s top about two centimetres above the soil’s surface. To enable for later watering, create a little moat around the mound, about 25 centimetres from the plant. A light cane can be used to secure the plant against wind damage if it is a little floppy.

How to plant?

  • Sow indoors from late April onwards for the earliest yields.
  • Sow in tiny pots filled with multi-purpose compost one at a time. Pots of yoghurt are an excellent option.
  • Sow the seeds on their sides about 1 inch deep.
  • Set pots on a warm windowsill in a propagator or clear plastic bag until seeds germinate. Remove the covers at this stage, but keep the heat on.
  • Because of their broad foliage and robust stems, young butternut squash plants are easy to handle but handle them carefully as you transplant them to the garden or allotment.
  • After all risk of frost has passed, harden them off for a week or so and then plant them out.
  • Alternatively, seed outside in May in pre-warmed soil under a cover. If both seeds germinate, sow two seeds per station and thin to the strongest seedling.



Butternut squash plants need to be kept weed-free and fed throughout the growing season because they are hungry plants. Pelleted chicken dung or a liquid fertiliser are also effective options. Around 15 weeks after sowing seeds, most butternut squash types will yield fruit.


Trim back the plant’s main stems when they reach 60cm in length so that the plant’s energy is focused on creating flowers and fruit rather than masses of leaves.


Plant natural wildflowers (foxgloves, sunflowers, and echinacea) near your vegetable plot to attract pollinators like bees. When bees collect nectar and pollen from wildflowers, they will also visit your vegetable blooms and pollinate them, resulting in more fruit settings and increased production.


Tender fruits can be damaged by soil-borne pests or fungal diseases, so raise them off the ground with bricks, tiles, or even polythene.

Pests and Diseases

After planting out, young plants will require protection from slugs, snails, and aphids. Butternut squash can succumb to powdery mildew and cucumber mosaic virus later in the season. Keep your plants well-watered and look for disease-resistant varieties.


Allow the fruit to fully grow on the vine before harvesting pumpkins and winter squashes for winter storage. Make sure you pick them before the first frost. Butternut squash has a lengthy shelf life and keeps well over the winter.


Does butternut squash need a trellis?

Butternut squash, like all winter squashes, ripens on the vine, and the fruits mature over weeks, not days. It has tenacious vines that scramble up to ten feet in length. The vines’ tendrils will readily twist around a tomato cage, but the fruit itself may require support if grown on a trellis.

What is the best way to grow butternut squash?

You should start growing butternut squash indoors about six weeks before the final frost in your location. Plant in good soil in a sunny window or greenhouse, as you would most vegetables, then transplant to the garden once all risk of frost has passed. Before transplanting, remember to harden off the seedlings.

What can I plant next to butternut squash?

Corn, lettuce, melons, peas, and radish are all good companions for squash. Planting near Brassicas or potatoes is a bad idea. Borage is supposed to help squash grow and taste better. Several squash pest insects are attracted to marigolds and nasturtium.

How do I know when my butternut squash is ready to pick?

When the skin is rigid (can’t be punctured with a thumbnail) and evenly tan in colour, butternut squash is mature (ready to harvest). Leave a 1-inch stem on each fruit while harvesting.

Should you cut back butternut squash?

Early autumn is when butternut squash plants are ready to harvest. Squash plants can yield a lot of fruit once they get going. Trimming back your butternut squash vine, if it has taken over your garden, will not affect the squash yield and may even be advantageous.

What if you pick butternut squash too early?

The texture will be too stiff and the sugars will not have developed if you pick them too early. The squash will get too mushy if you wait too long to harvest it. Butternut squash will have green vertical lines on them when they first appear on the plant. The stem end of the squash will transition from green to brown as it matures.


How to grow butternut squash vertically?

To grow butternut squashes, you will need a trellis. Squashes, on the other hand, can be taught to mature and behave. However, you’ll need to put in some effort – with the help of a solid trellis – to ensure that they can provide you with a constant supply of squash throughout the summer and fall. This is usually more effective when used in smaller spaces.

How to grow butternut squash in a small space?

If you don’t have a lot of space, growing squashes vertically is the natural solution. The simplest method is to train them to climb a trellis. A basic one-piece trellis can be anchored to a robust fence or a sun-facing wall. Plant your squashes at the same spacing as they would grow if left on the ground.

Butternut squash growing stages

The seeds will sprout in around ten days. Thin out the weakest plants when they’re about 6 inches (15 cm) tall, leaving three plants per hill. Because the fruit maturation period for butternut squash is typically 110-120 days, it’s recommended to sow your seeds inside to give them a head start if your season is short.

Butternut squash growing problems

-Fruit drop is a typical problem with butternut squash, as well as any other summer or winter squash. Poor pollination is most likely the cause of young fruits turning yellow, shrivelling, and falling off the vine.

Why does my squash flowers but no fruit?

If your squash plant produces a lot of flowers but no fruit, or if the fruit stops growing when it’s little, you’re probably dealing with a pollination problem. Most squash plants are monoecious, meaning they produce both male and female flowers on the same plant. Pollen from male flowers must be physically transferred to female flowers by bees in order for fruit to form. The bees usually do a great job, but if there aren’t enough bees in your location, you can end up with fewer squashes than you expected!


Amit Kumar