Growing Jarrahdale

General

• Jarrahdale pumpkins grow in United States Department of Agriculture zones 2 through 11. They need sun to full sun and are tolerant of both heat and humidity. The vines require a large space because they grow 18 inches high and up to 30 feet wide. The ripe pumpkins weigh 6 pounds or more each.

Soil Needs

• Jarrahdale and other pumpkins prefer a loamy soil with good drainage and a pH value from 6. to 6.5, or slightly acid. Correct an overly acidic soil by adding dolomite or lime six weeks or more before sowing seed. Jarrahdale pumpkins also like added compost, but give organic materials a chance to decompose before sowing seeds. Dig or plow the soil 8 to 10 inches deep and break it up fine to prepare for the deep roots of the vine.

Planting

• Plant the pumpkin seeds when the outdoor soil temperature reaches 65 degrees Fahrenheit. Plant four to six seeds 1 to 2 inches deep, in mounds separated 4 feet apart. After the seeds sprout, reduce each mound to two plants. Move the transplants to new rows from 4 to 6 feet apart, spacing individuals 2 to 3 feet apart. Alternatively, start the seeds indoors in flats early in the season. Transplant them outdoors when the soil has become warm enough.

Water and Fertilizer

• Sufficient water is essential for pumpkins to flower and develop fruit. Infrequent but deep watering by drip irrigation will produce the best results. Reduce evaporation and discourage weeds by mulching around the plants. When they grow runners, fertilize the plants with 1 to 2 tablespoons of 34-0-0 fertilizer for each mound. Keep the fertilizer at a distance of 6 inches or more from the plants.

Pests

• Various types of pests attack Jarrahdale pumpkins. Treat aphids with a strong water spray or insecticidal soap. Treat cucumber beetles with chemicals when they first appear. Examine the plants for squash bugs, and pick them off. Prevent mildew by planting resistant stock and by avoiding excessive wetting of the vine or foliage. If fungus appears, apply fungicide early before it destroys the entire plant. When the fruit ripens, protect the pumpkin patch from large animals such as deer and rodents.

Harvesting

• Jarrahdale pumpkins mature approximately three months after planting. Harvest the fruit when it has an even color and the rind feels hard. The vines also start to die when the fruit is ready. Cut each pumpkin from the vine with a knife, keeping a piece of the stem on the fruit. Store the mature Jarrahdale pumpkins in a cool, dry location with adequate air circulation.