How To Grow Butternut Squash

How To Grow Butternut Squash

It is easy and rewarding growing butternut squash in your garden.

Butternut squash has a fairly long season of 110 – 120 days. It is a winter squash and can be stored for long periods.

beautiful butternut squash Squash plants can create shade for roots of other plants and are one of the sisters in a Three Sisters Garden.

Starting Butternut Squash Seeds

Starting seeds indoors is easy and is a great way to get a head start on the gardening season.  Butternut squash seeds need to be started indoors 2 – 3 weeks before your final frost of spring. This assures a harvest of beautifully ripened squash.

If you live in a zone with long hot growing seasons you can direct sow into the garden.

Sow seeds in 4 inch containers using store bought potting soil. Plant 2 seeds per pot at a depth of 1/2 inch. Water carefully to not disturb the seeds. Place the containers in a tray and set in a warm sunny location.

All seeds need warmth to germinate. If you have fluorescent grow lights, place the seeded pots under the lights keeping them fairly close to the surface. If you have a heated seed starting mat, use it as a supplementary heat source.

Keep the soil moist but not too wet. A clear cover placed over the seeded containers help with germination. The seed should start to germinate within 7 – 10 days. Once the seeds are growing the cover can be removed from the plants. Water as needed, do not allow the tender seedlings to dry out.

Hardening Off The Plants

Any plants started indoors must be hardened off before being planted outdoors. This period takes around 2 weeks for the plants to acclimate to the outdoor weather conditions.

Once the days are warm, set the squash seedlings outside in a sunny, wind protected location. Start with having them outside a few hours a day. Over the two weeks extend the time they are left outside by an hour every day. By the end of the second week they can safely be transplanted into the garden provided the weather is warm and all chances of frost have passed. Butternut squash seedlings do not do well in the cold, make note of the forecast before planting outdoors.

Planting Squash In The Garden

The first step is to prepare the growing site. Work the soil well adding amendments like peat moss and compost. The addition of sand should be considered if the ground is compact. Sand will help loosen the soil and creates better drainage, important in any garden.

Squash need room to grow, so dedicate a nice sized patch. If you are considering growing a Three Sisters Garden, you can refer to the planting options here. Squash requires full sun so keep that in mind when selecting a growing location.

growing butternut squash

Squash plants spread across the ground so row planting is not necessary though it is always an option. Once the area has been worked, plant the indoor started seedlings. Warmer areas with nice long seasons squash can be directly seeded.

For the planting spots, create 12 inch tall mounds with the soil, a foot wide is the perfect width. Smooth out the center of the mound leaving a ridge around the outer edge. For direct seeding place 3 seeds in the soil of each mound at a depth of 1 inch. Water the seeds well.

Create the same sized mounds for butternut squash transplants. Make a hole larger than the container the seedling is planted in. With one hand supporting the plant, turn the container over and give it a light tap or squeeze the sides gently to remove the seedling. Place it in the planting hole and firm up the soil around the stem filling any air pockets. Water the transplants well.

butternut squash in the garden

Caring For Butternut Squash

Mulching the squash patch is a great way to conserve water and acts as a barrier to weeds. Apply it immediately after planting.

Because butternut squash is a vining plant you can grow it on a trellis in certain situations. Butternut squash can get quite heavy and will require extra support for each squash. When growing on trellis select a dwarf variety of squash.

Apply a 20-20-20 fertilizer early in the season and again when blooms start. There are many water soluble types available. Follow the manufactures direction for mixing.

Flowering and Fruiting

Butternut squash has both male and female flowers. The male flowers will be the first to bloom followed by female flowers. The female flowers need to be pollinated with pollen from the male flowers. This usually happens by visiting bees carrying pollen from one flower to the next.

You can help the pollination process by using a paint brush to move male pollen to the female flowers. The male flowers are on long stalks. The female flowers have tiny bulbs at the base of the flower which will develop into a squash once pollinated. Simply use the paint brush to collect pollen from the male flowers. Take the pollen filled paintbrush and paint all around the inside the female flowers.

Harvesting Squash

Depending on when you started your squash will determine when it can be harvested. Winter squash is a late season harvest usually in mid to last September through to October.

Leave winter squash on the vine mature. The rind will become hard and develop a nice beige colour. You can test for ripeness by trying to piece the skin of the squash with your fingernail. If you can piece the skin, the squash is not mature.

Once the rind has completely hardened you can harvest the squash. Use a sharp knife to cut through the stem. It is important to leave an inch to two inches of stem on the ripened squash.

An important note, if the weather threatens frost and the squash is not quite ripe yet, harvest it. It will not survive the frost.

 Curing Butternut Squash

Curing squash is important for long term storage. Place the squash someplace dry and warm. This helps harden the skin as it dries out and aids in preventing rot. As the squash cures it creates a sweeter flavour.  If possible place the squash on racking, this creates good airflow.

Check on the squash during the curing stage. Monitor the fruit for any soft or dark spots. Move any affected squash and use immediately, remembering to save the seeds for next years crop.

Remove cured squash after two weeks.

prepping butternut squash

Storing Butternut Squash

Store fully cured squash in a cool, dry, dark location.

You can also freeze butternut squash for long term storage. Peel the squash and cut into chunks.

This post was written for and first shared at Earth, Food and Fire.

Hot To Grow Butternut Squash

Published by Redawna

Garden & Food Writer/Educator/Photographer. NFT artist. Management Professional. Community Builder. Entrepreneurial spirit.

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