Pumpkins

24.05.17

Pumpkins belong to the Cucurbitaceae plant family which also includes cucumbers, melons, zucchini and gourds. The cucurbita species commonly referred to as pumpkins are Cucurbita maxima and Cucurbita moschata, however, these species are traditionally considered as two separate groups. Cucurbita maxima are traditionally referred to as pumpkins and Cucurbita moschate as grammas, however in Australia these species are grouped and popularly called pumpkins.

Overview

Pumpkins are an annual vigorous prostrate vine with an extensive root system and usually put down peg roots to secure the plant and have tendrils that wrap around other plants to prevent the vines from being blown around. They have separate male and female flowers on a single plant.

There are a range of pumpkins that can be grown in Australia and the particular variety will depend on the climate and market demand for each season. Both C. maxima and C. moschata can be grown in Australia with C. maxima generally preferring cooler climates and C. moschata more tolerant of hot, humid climates; however there are varieties of each species that will grow in the opposing climate. The species C. maxima includes Jarrahdale, Queensland Blue and Kabocha (often called buttercup squash); and C. moschata includes butternut pumpkin and varieties referred to as Japanese pumpkin. Crosses between the two species include Ken’s special and OOAK.

Pumpkins are commercially grown in every state and territory in Australia (except the Australian Capital Territory). Pumpkins are often grown by broadacre farmers as an opportunity crop, as they do not require as much labour as other vegetable crops, and they can be harvested at one time and stored.

Pumpkins are consumed boiled, steamed, baked, fried or pureed in sweet or savoury dishes. The fruit is a good source of carbohydrate, rich in energy, fibre, beta carotene and vitamin C. Most of the pumpkins produced in Australia are consumed on the domestic market.

The pumpkin industry is represented by AUSVEG, the national peak industry body representing Australian vegetable and potato growers.

Facts and figures

  • Pumpkins are a member of the Cucurbitaceae plant family and are related to melons and zucchinis
  • They are an annual vine requiring large amounts of water to achieve optimum yields
  • Pumpkins are grown commercially in all states of Australia
  • They are often grown by broadacre farmers as an opportunity crop
  • Pumpkins can be sold direct to the fresh produce market, to processors or stored

Production status

Total Australian pumpkin production is around 120,000 tonnes from 1,058 growers under 6,986 hectares of cultivation, worth a gross value of AU$76.2 million. They are grown commercially in every state and territory in Australia (except the Australian Capital Territory) with the majority of production in New South Wales and Queensland followed by Western Australia.

Generally, Jarrahdale and Japanese pumpkins comprise about three quarters of the total production and nearly one quarter of the remainder is butternuts.

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Map of current and potential growing regions

Uses

Pumpkins are a very versatile vegetable (strictly they are really a fruit) that can be boiled, steamed, baked fried or pureed; and consumed in sweet and savoury dishes.

The fruit of the pumpkin is a good source of carbohydrate, rich in energy, fibre, beta carotene and vitamin C.

Production Requirements

Growing regions

Pumpkins are grown commercially over summer in New South Wales, Victoria, Queensland, Western Australia and Tasmania and during the dry season (May to September) in the Northern Territory. Queensland is Australia’s largest producer of all types of pumpkins, closely followed by New South Wales, where half of that state’s production is based in the Murrumbidgee Irrigation Area.

Soil type

All varieties can grow and yield well on heavy soils that are not suited for other vegetables, however the ideal soil for growing pumpkins is a fertile, well-drained loamy soil, with a soil pH(water) of 6.0–7.2. Pumpkin roots can grow down to a metre deep, so drainage is important as pumpkins will not tolerate waterlogging. Organic matter should be added to sandy soils to improve fertility and water holding capacity. They are sensitive to salinity; they can tolerate up to 1.5dS/m before productivity will be affected.

Climate

Pumpkins can be grown in a range of climates with varieties suited to cool climates or warm climates. Temperatures of 20–35°C are ideal for maximum production; conditions above 35°C and low humidity will reduce yields. Members of the Cucurbitaceae plant family are frost sensitive and require a frost-free growing period of four to five months.

At planting, a soil temperature above 16°C is required for seeds to germinate and germination is accelerated as the soil temperature increases.

Varieties

Variety selection will depend primarily depend on climate and then on intended market. There are many varieties available and many types within the varieties. A short list is provided below outlining some of the more commonly known varieties. Seed distributors are a source of further detail on pumpkin varieties and types as well as suppliers of seeds.

Species Variety Attributes
C. maxima Jarrahdale Fruit size: 6-8kg

Time to maturity:
18 to 20 weeks

Queensland blue Fruit size: 4-7kg

Time to maturity:
20 weeks

Long storing pumpkin

Kabocha (also called Buttercup Squash) Fruit size: 1.2-2.0kg

Time to maturity:
13 to 17 weeks

C. moschata Butternut Fruit size: average 2kg

Time to maturity:
15 to 18 weeks

Japanese Fruit size: average 4kg

Time to maturity:
20 to 25 weeks

Kent special Fruit size: average 4kg

Time to maturity:
20 to 25 weeks

Hybrids OOAK Fruit size: average 4kg

Time to maturity:
20 to 25 weeks

Ken’s Special hybrid Fruit size: 3 to 4kg

Time to maturity:
20 to 25 weeks

High yielding

Planting and crop management

An appropriate crop rotation should be followed when growing pumpkins, as crops grown in succession in the same field, without break crops in between, will be more vulnerable to pests and diseases, than pumpkins grown in a well-planned rotation.

Good ground preparation is important for high yields and ripping may be necessary if the soil is compacted. The soil should be worked to a suitable tilth; and all organic matter should be incorporated into the soil well before planting, to ensure it has broken down.

Pumpkins are sown over summer in New South Wales, Victoria, Queensland, Western Australia and Tasmania and during the dry season (May to September) in the Northern Territory. The crop is usually established by direct seeding but some crops are sown as transplants. Plant density will affect the final fruit size and depending on the variety are sown at rates from 2,000 to 7,000 plants/ha. Seed should be treated with a fungicide before sowing. Pumpkins also need to be protected from the wind, generally through the use of windbreaks.

Irrigation is generally used to achieve maximum yield and drip, overhead and furrow are used for pumpkin production. Generally, a pumpkin crop requires 4–8ML/ha of irrigation water from sowing to harvest; but this will vary according to soil type, method of irrigation and weather conditions. Plastic mulch may also be used to reduce water loss.

As pumpkins have separate male and female flowers on the same plant, insect pollinators are required. It may be necessary to install beehives in a pumpkin crop to increase fertilisation and as a guide generally two to three hives per hectare is recommended. Growers should be vigilant about noting insect activity in the crop, and reduce pesticide application at critical times or apply when insect activity is at its lowest, usually late afternoon.

Further information on planting and crop management of Japanese pumpkins can be sourced from the New South Wales Primefact Pumpkin production, the Department of Agriculture and Food Western Australia Agnote Growing pumpkins in Western Australia, the Northern Territory Government growing note Butternut Pumpkin, and from AUSVEG.

Weeds, pests and diseases

Weed control is most important during the establishment phase of a pumpkin crop, and once established, pumpkin grows vigorously and is quite competitive against weeds. Weeds can be controlled with the use of mulch, hand weeding, shallow cultivation and herbicides. Check for appropriately registered herbicides with local state departments of agriculture before applying to any crops.

Pumpkin beetle, whitefly, melon aphid, cutworms, heliothis grubs, spider mites, root knot nematode, caterpillars and nematodes all have the potential to cause problems in pumpkins. Insecticides are available for all these pests but integrated pest management is recommended, for example being susceptible to root knot nematodes, pumpkins should not be grown in rotation with other crops that host nematodes.

The most significant diseases affecting pumpkins are downy mildew, powdery mildew, black spot, Fusarium wilt, cucumber mosaic virus, papaya ringspot virus, watermelon mosaic virus and zucchini yellow mosaic virus can all affect pumpkins. There are a number of fungicides and insecticides registered for treatment of diseases in pumpkins, however good crop hygiene and integrated pest and disease management practices should be adopted as a standard method for managing pests and diseases.

Further information on weeds, pests and diseases including their management in pumpkin crops can be sourced from the NSW Industry & Investment Primefact Pumpkin productionGrowing pumpkins in Western Australia and the Cucurbits crop protection page on AUSVEG.

Infrastructure Requirements

Standard horticultural equipment, including bed formers, planting equipment and irrigation infrastructure, can be used to produce pumpkins.

Storage facilities may be necessary to maintain the product in cool, dry conditions.

Harvesting & Processing

Depending on the variety, pumpkins can take 14-25 weeks to reach maturity from planting. Usually the crop is left to mature on the vine and harvested when the vine has completely died off – when the stalk is cracked and corky.

The fruit is harvested by hand, and the length at which the stem is cut will depend on the variety and can range from 3-30cm to ensure that the fruit will keep. Pumpkins may be sold directly to market or can be stored for 4–6 months. They should be stored unwashed in a dry, well-ventilated and shaded area, or they may be stored in a cool room at 10–13°C and with a relative humidity of 70–90%.

Pumpkins can yield 12–40t/ha, with Jarrahdale being the highest yielding type, followed by Japanese pumpkins.

Further information on harvesting and processing of Japanese pumpkins can be sourced from the New South Wales Primefact Pumpkin production, the Department of Agriculture web page Growing pumpkins in Western Australia and from AUSVEG.

Markets & Marketing

Farmers sell pumpkins on a price per tonne or kilogram basis directly to the fresh produce market or to a processor. If selling to a processor, a contract price may be set at the beginning of the season or sold at market price at the time of harvest.

If selling direct to the fresh produce market, the pumpkins are either sold to a local packer or the farmer can manage the packing on-site and then sell directly to the market. Pumpkins can be packaged and sold in bulk containers, cartons or netted bags and if selling to a processor are delivered in bulk containers.

Some pumpkin production is exported, mainly to Japan. However, as pumpkin is a designated host for fruit fly, only Tasmanian pumpkins have been exported to Japan due to quarantine restrictions. In volume terms, the Australian share of the total Japanese import market for pumpkins has averaged less than 1%, the market being dominated by New Zealand (62%) and Mexico (35%).

Some growers value-add to the extent that large pumpkins are often marketed cut into segments and wrapped in cellophane. Before sale, the pumpkins may also be skinned, diced and wrapped for ready culinary use.

Risks & Regulations

Risks/challenges

As with all agricultural pursuits, risk is inherent in vegetable growing and can include:

  • the crop failing to establish or mature properly due to adverse weather events, thus resulting in reduced harvest tonnage and/or poor quality product
  • commodity prices falling during the growth period impacting on the returns projected at planting
  • not recouping the costs of inputs and capital invested in the crop, like fertiliser or the costs of running large equipment, if the crop fails.

For pumpkins specifically, there is a production risk of the crop suffering powdery mildew, which can be controlled by fungicides but can still affect input costs and yield.

Regulatory considerations

The regulatory considerations that apply to all Australian farms, including laws applying to chemical use and management, occupational health and safety and transport (including machinery movements and the loading/unloading of harvested grain), apply to vegetable growing operations.

Currently there are no industry-wide product descriptions or quality standards developed for pumpkins. Some vegetable producers choose to participate in Freshcare, which is currently the largest Australian on-farm assurance program for fresh produce for on-farm food safety and quality and environmental certification services.

When growing and packaging produce for food markets, consideration should be given to food standards regulations. Further information can be found at the websites of Freshcare, HACCP and Food Standards Australia New Zealand.

Publications

Publications/information

Pumpkin production New South Wales Primefact 964 (2009)

Growing pumpkins in Western Australia Department of Agriculture

Butternut Pumpkin Growing Note V1, Northern Territory Government

Pumpkins Agriculture Victoria Note AG0283

Crop Protection – Cucurbits AUSVEG

Other resources

Freshcare is an industry owned, not-for-profit on-farm assurance program, established and maintained to service the Australian fresh produce industry.

HACCP Australia is a leading food science organisation specialising in the HACCP Food Safety Methodology and its applications within the food and related non-food industries.

Food Standards Australia New Zealand is a bi-national Government agency. They develop and administer the Australia New Zealand Food Standards Code.

Industry Bodies

AUSVEG is the national peak industry body representing the interests of Australian vegetable and potato growers

Image Gallery

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Pumpkin on the vine

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Jarrahdale pumpkin

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Growing pumpkins

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Butternut Pumpkin