Fascinating facts and figures: pumpkins

Harvesting pumpkins

  • Botanical name: Mainly Cucurbita pepo, giant forms are derived from Cucurbita maxima
  • Origins:  Central and North America
  • First cultivated:  Seeds have been found on Mexican archaeological sites, dating back to 5,000 - 7,000BC
  • Skill level: Ideal for both beginners and experienced gardeners
  • Preferred location and conditions: Full sun on fertile, moisture-retentive soil with plenty of added organic matter. Avoid shallow soils
  • Good for containers: Smaller varieties such as 'Small Sugar' and 'Munchkin' grow well in large patio pots and growing bags
  • Harvest time: Autumn, before first frost strikes
  • Possible problems:  Powdery mildew - usually due to dry soils and humid conditions. Poor fruit set - usually due to cold conditions at the start of the season and is usually remedied once temperatures increase
  • Health benefits: Low in calories, high in vitamin A and C, minerals and health boosting beta-carotene

Potted history

Pumpkins are actually forms of winter squash and are now grown on all continents other than Antarctica. Early pilgrim settlers were introduced to the pumpkin via Native American cultivation. Many tribes used the 'Three Sisters' planting method, setting them amongst sweet corn and climbing beans, each bringing benefits to the others.

Record-breaking pumpkin at Hyde Hall 2016Pumpkins remain an important commercial US crop, with 680,000 tonnes produced each year. The harvested fruits are an iconic food ingredient in the US, with pumpkin pie a staple in Thanksgiving and Halloween celebrations. In the UK, culinary use is second to decorative use at Halloween, even though all parts of the plant - fruit, seeds, flowers and leaves -  are edible. Competitive growing at local and national level remains a popular pastime in the UK.

The record for the biggest outdoor UK pumpkin was set in 2016 with a 605kg giant grown by gardener Matthew Oliver at RHS Garden Hyde Hall in Essex. The biggest grown under glass in the UK was produced by Stuart and Ian Paton in the New Forest in 2016, weighing a staggering 1022kg.

Why grow pumpkins

Pumpkins are a great introduction to grow-your-own for children.The large seeds are easy to work with and the  swelling fruits provide a real sense of achievement, leading to confidence with other crops. The harvest of course leads to the fun activity of carving and decorating for Halloween. Pumpkins grow with few problems, given a sunny spot sheltered from cold winds, and while they take up a good amount of space on the vegetable patch, they can be trained along the ground between rows of sweet corn and other tall crops. Some of the best pumpkins are grown directly on the compost heap.

Planting and growing:  

Seeds can be sown outdoors in late May-June, but in colder regions it is best to start them under cover at 18-21°C (65-70°F) and plant out in June after hardening off the seedlings (place plants outside by day and bring in at night for a week before planting). Earlier crops can also be had by sowing indoors from mid April.

When planting out, create deep pockets of compost in the soil, around a spade spit deep and wide, and set plants into the compost. You can also grow pumpkins in growing bags or containers (at least 45cm / 18in wide). Plant one or two per growing bag, or one per container.

Smaller varieties with prolific fruiting can be left to grow and crop, but to get the best results with larger fruiting varieties, only allow four or five fruits to mature on the plant. After first fruit set, offer a high potassium feed every 10-14 days to support swelling growth.

Keep fruits off of the soil by supporting them with straw, sacking, roof tiles, stone slabs or similar. Allow the fruits to ripen on the plants and harvest before the first frosts of autumn. Allow skins to harden in the sun if you plan to store over winter.

Text provided by Mr Fothergill's.

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