6. Pollinate the flowers
In late June or early July, flowers needs to be pollinated in order for pumpkins to develop. Pollination may occur naturally through bees and other insects in the garden, but Chenier and his fellow giant pumpkin growers hand-pollinate the female flowers with male flowers from other plants.
You can tell the difference between a male and female flower by looking at the base of each bloom. If there is a small bulb resembling a tiny pumpkin, then you know the flower is female. If the bulb is missing, then the flower is male.
Once a chosen female flower develops into a pumpkin, the growth is tracked to see if it will reach certain benchmark levels that usually indicate a giant pumpkin in the making. Professional growers estimate the final size of their pumpkins by comparing measurements with a growth chart filled with data collected by GVGO members. The chart allows growers to compare the growth rate of their current crop to giant pumpkins from previous seasons that became record holders.
7. Choose your champion pumpkin
Check your vines every few days to see when new pumpkins are developing. In the beginning of July, choose one or two of the fastest-growing pumpkins and remove all of the others from the vine. By thinning out the crop, you’ll be directing all the energy and nutrients from the plant to your potential champion.
8. Caring for your vines
Many things can go wrong in the pumpkin patch during the growing season. Home gardeners need to be wary of several pests and diseases. Animals like raccoons, chipmunks, and moles may eat or mark the pumpkins. Insect pests like cucumber beetles, aphids, squash vine borers among other insects can also wreak havoc on the plants. By being vigilant, you’ll be able to deal with any pests and diseases before an invasion occurs.
9. Feed and fertilize
Since pumpkins have shallow roots, the plants need a generous amount of water, especially during the hot summer months. It’s best to water them in the early evening, but allow the plants to dry out before nightfall. If the moisture is not kept even, the pumpkin might split after a heavy rainfall, which can cause a growth spurt. Giant pumpkins have an unquenchable thirst, and some of these monsters can use as much as 100 gallons of water a day during peak growing season. On average, giant pumpkins grow about 30 pounds a day, but some giants can gain as much as 60 pounds in twenty-four hours.
Pumpkin growers fertilize their plants with liquid kelp and fish, molasses, humic and fulvic acid, and calcium, as well as homemade compost teas, which are very easy to brew.
10. Harvest your giant pumpkin
When the weather starts to get cold, you’re ready to harvest your giant pumpkin. The last thing you want after all your hard work is to leave your pumpkin on the vine to freeze. Depending on the size of your pumpkin, you may need a few friends to help move it. Roll the pumpkin onto a blanket and have each person lift a corner to move it to a location where you can impress your friends and family.
Competitive growers continue to grow their pumpkins into September and October, or until the weekend of the official weigh-in, In Ontario, the largest weigh-off is the Port Elgin Pumpkinfest, where the grand prize for the heaviest pumpkin is $5,000. To move these giants, a special lifting device is used to cradle the pumpkin during harvest and moved to a padded pallet for transportation.
The secret to growing a giant pumpkin is patience and constant attention. Home gardeners should have some fun along the way, and Chenier suggests that this gardening adventure should be taken slowly and steadily. To see more giant pumpkins grown by the professionals, visit the Giant Vegetable Growers of Ontario (www.gvgo.ca).
Anja Sonnenberg is a horticulturist who writes about the fun she has in her garden on her blog, A Gardener’s Playground.
Images courtesy of Giant Vegetable Growers of Ontario
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