How to Grow Large Pumpkins
Master how to grow big pumpkins, and you can trim some fall expenses from the family budget. Pumpkin vines are productive, and you’ll have ample fruit for carving and creating seasonal decorative displays that can last all the way through Thanksgiving—and fill a pie or two along the way. Discover how to grow large pumpkins with these simple steps.
First, decide what you want: a large pumpkin for carving or decorating or a ribbon-earning giant. Large pumpkins may not earn you fame at the local pumpkin festival, but they’ll score big points with your family—and likely make your house the envy of the neighborhood for its homegrown harvest.
To grow a big pumpkin, purchase seed that promises the harvest size you want. For modestly large pumpkins in the 25- to 35-pound range, search out seeds of the varieties Ol’ Zebs, Cinderella, or Gold Rush. If your sights are set on a 40- to 50-pound pumpkin, get seeds for Mammoth Gold, Burpee Prize Winner, or Big Moon.
Follow planting instructions on the seed packet. As soon as vines start running or spreading, along the ground, make sure your plants have enough water. Pumpkins are thirsty, and when you’re growing bigger fruits, you need to provide water if it doesn’t rain. Avoid using an overhead sprinkler, because that can spread diseases. Instead, use a soaker hose. As vines fill in, you won’t be able to see the hose, so don’t worry if it’s not the prettiest sight early in the growing season.
Check plants regularly for any signs of diseases or pests. Each leaf is very important and vital to producing large pumpkins. If you spot a problem on one leaf, it most likely will spread to another. Diagnose and treat problems as soon as you see them.
At each point along the stem where a leaf appears, a pumpkin vine can also produce secondary roots. Encourage these roots by heaping soil over stems beside leaves and watering for a week or two. Do this in a few places away from the main stem. Secondary roots help your vine support multiple large pumpkins simultaneously.
Pumpkin vines grow with one main vine and several branches. Keep an eye on the branches, and prune the tips of these vines when they’re 10 to 12 feet long. Bury the cut tips. Pruning the vines tricks the plant into sending more water and nutrients to the developing fruits.
To grow only a few large pumpkins, thin ripening fruit. An easy way to do this is to allow only one or two pumpkins to remain on each main branch of the vine. Use hand pruners to snip away stems of smaller pumpkins. Bury these in your compost pile or vegetable garden to feed worms and enrich soil.
Consider slipping a wafer of straw or an inverted terra-cotta saucer beneath young pumpkins to protect the ripening side from attack by soil insects. Harvest pumpkins when rinds show good color all over or just before frost, whichever occurs first.