Planting pumpkins: when, where & how to grow pumpkins

Edward
Edward
Edward
Edward

With a passion for growing installed at an early age, I have always been happiest outdoors in nature. After training as a professional gardener and horticultural therapist, I currently run horticultural therapy and community kitchen gardens in the UK, helping others access the many physical and mental health benefits of growing vegetables, fruit and plants.

Favourite fruit: apples and pears
Favourite vegetable: asparagus

Widely cultivated for their culinary and ornamental uses, pumpkins are easy and fun to grow at home. Learn all about planting and growing these tasty autumnal fruits. 

planting a pumpkin seedling
Growing pumpkins from seed can be cost-effective and rewarding [Photo: Miriam Doerr Martin Frommherz/ Shutterstock.com]

As a key part of the growing calendar, pumpkins (Cucurbita) can be relied upon to provide a welcome harvest of autumnal fruits. Whether you choose to grow them for their delicious flesh or for decorating come Halloween, there are many pumpkin varieties available to choose from. Read on to discover everything you need to know about planting pumpkins, from when to sow pumpkin seeds to their preferred location.

Planting pumpkins: the ideal location

Pumpkins can take up a lot of growing space, and with some growing up to 5m in length, they can need a substantial area to thrive. However, not all varieties mature into large plants. For example, where space is limited, you can grow the smaller Uchiki Kuri, which is technically a squash, in a large container or even vertically. Either way, pumpkins require a sunny and sheltered location so that their fruits have enough time to ripen before the first winter frost arrives. 

Pumpkins ripening on a vine
Some pumpkin varieties need a lot of space to grow and produce fruits [Photo: Mila Che/ Shutterstock.com]

Along with ample space and sunlight, pumpkins require a fertile and moisture-retentive soil to grow well. A sandy loam soil is ideal, as long as it holds some moisture. Nevertheless, any sites that are prone to waterlogging should be avoided, as this can lead to the roots rotting. As hungry plants, it is advisable to enrich the soil before planting; to do this, add some well-rotted manure or compost. For example, you could work our Plantura Organic Enriched Compost into the garden bed. It is high in nutrients to support the pumpkin plant’s vigorous growth and luckily it is peat free as well. 

Organic Enriched Compost, 40L
Organic Enriched Compost, 40L
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star-rating star-rating star-rating star-rating star-rating
(5/5)
  • Perfect for all crops and ornamental plants with a high nutrient requirement & for raised beds
  • Improves soil quality & promotes healthy root growth
  • Peat-free & organic soil: CO2-saving composition
£16.99

When to plant pumpkin seeds

Pumpkin seeds and young plants are readily available to buy from garden centres and online. If you choose to grow pumpkins from seed, you can either sow them indoors or outdoors. To give the plants a head start, which is advisable in colder parts, you can sow pumpkin seeds indoors in April somewhere warm. You can also sow pumpkins outdoors directly where they are to grow, but only once all risk of frost has passed. This can be any time between late May to early June depending on your location. 

Sowing pumpkin seeds in soil
Once all risk of frost has passed, you can sow pumpkin seeds directly outside [Photo: lovelyday12/ Shutterstock.com]

Tip: pumpkins require a long growing season to fully ripen before the end of autumn. To give your pumpkins a helping hand, sow the seeds undercover in April and plant them out once the soil has warmed up and all risk of frost has passed.

How to grow pumpkins

Pumpkin seeds need to be kept at a temperature of around 18 to 21 °C to germinate. You can achieve this by either using a propagator or a warm and sunny windowsill. To sow your pumpkin seeds indoors, fill a small pot or module tray with a multi-purpose or seed-sowing compost mix, either is fine as the seeds are large. You can use our Plantura Organic Herb & Seedling Compost to start pumpkins seeds, as it has been specially formulated to promote root growth; plus it is peat-free, making it environmentally friendly. Sow one seed per cell or pot on its side at a depth of 1cm before covering with a propagator lid or a clear cling film to control moisture levels. Briefly uncover the pots daily to refresh the air inside and remove the lid once the seedlings emerge. Water and keep the soil moist, but not wet until the seeds have germinated.

Organic Herb & Seedling Compost, 20L
Organic Herb & Seedling Compost, 20L
star-placeholder star-placeholder star-placeholder star-placeholder star-placeholder
star-rating star-rating star-rating star-rating star-rating
(4.8/5)
  • Perfect for herbs as well as sowing, propagating & transplanting
  • For aromatic herbs & healthy seedlings with strong roots
  • Peat-free & organic soil: CO2-saving composition
£12.49

Once the pumpkin seeds have germinated, you can reduce the temperature to around 16 to 18 °C and grow on keeping the soil moist. In May, gradually harden the plants off before planting them outdoors. Before planting your pumpkin plants out, remove any stones and weeds and feed the soil to prepare the site. To enrich the soil, incorporate some garden compost or well-rotted manure and add a slow-release organic fertiliser.

Pumpkin seedlings on windowsill
Grow pumpkin seedlings somewhere warm indoors before gradually hardening off to plant outside [Photo: nkjunky/ Shutterstock.com]

Depending on the variety, pumpkin plants need to be spaced 1m to 3m apart. Although not strictly necessary, you can plant your pumpkins on slight mounds of soil to promote drainage. Once planted, water the plants in thoroughly and irrigate frequently to keep the soil moist. 

If space is limited, you can grow smaller pumpkins in large containers around 40cm wide or in raised beds to trail over the sides. However, when grown this way, the pumpkin plants will need more frequent watering to prevent the soil from drying out. Instead of the vines trailing over the ground, you can also grow some pumpkins vertically up a support or trellis.

Planting a pumpkin in soil
For the best harvests, grow pumpkins in fertile and moisture-retentive soil [Photo: Novitskaya Olga/ Shutterstock.com]

Similarly, you can sow pumpkin seeds directly outdoors in early June. To sow direct, sow 2 to 3 seeds on a prepared site and water in. Once germinated, remove all but the strongest pumpkin seedling and grow on with slug and snail (Gastropoda) protection measures in place. 

Tip: along with an enriched soil, pumpkins benefit from being fed throughout the growing season. Find out all about pumpkin plant care including how and when to fertilise pumpkins in our specialist article.

A pile of smaller squashes
Smaller varieties of pumpkins and squash can be grown in large containers or pots [Photo: Elliotte Rusty Harold/ Shutterstock.com]

Pumpkin companion plants

When it comes to growing pumpkins near or with other plants there are some which are considered beneficial companion plants and others that should not be grown together. Along with companion planting, practising a crop rotation is also recommended to help prevent a build-up of soil-borne diseases and nutrient deficiencies. Here are some beneficial companion plants for pumpkins:

  • Lettuces (Lactuca sativa) are light-feeders and quick growing and can be picked before the pumpkins mature.
  • Peas (Pisum sativum) can be grown to help replenish nitrogen levels in the soil.
  • Calendulas (Calendula officinalis) can be planted to help attract pollinators.
  • Beans (Phaseolus) and corn (Zea mays) can be grown as part of the three sisters’ method. The beans return nitrogen to the soil, the corn provides climbing support for the beans and pumpkins and squash help deter weeds and prevent moisture loss.
  • Radishes (Raphanus sativus) are a quick-growing crop that can be harvested before the vines take over.

Crop rotation rules advise against planting pumpkins where other Cucurbita varieties have recently been grown including courgettes and patty pans (Cucurbita pepo). Along with this, pumpkins are heavy feeders, so it is not recommended to grow them after or with other hungry plants such as celeriac (Apium graveolens var. Rapaceum) or potatoes (Solanum tuberosum).

Three sisters method of growing
Beans, corn and squash can be grown together as part of the three sisters method [Photo: Rasmus S/ Shutterstock.com]

When stored correctly, pumpkins can keep for several months over the winter. You can read more on how to harvest and store pumpkins in our separate article.