If you grow pumpkins primarily to use them for fall decorations or to be able to say you grew your own jack-o-lantern, you'll want to grow at least a few big ones. Here are a few tips for growing big pumpkins in your garden.
1. Select the Right Variety
You can't make a pumpkin that is destined to be small into a huge pumpkin, no matter how hard you try, so the first thing to do is select the right variety. For nice, large pumpkins, look for 'Connecticut Field,' 'Howden,' 'Big Max,' or 'Mammoth Gold.'
2. Give Them Plenty of Room
Give each pumpkin plant at least five square feet in your garden to allow plenty of room for the vines to spread and a good open area to allow you to check to see how your pumpkin is coming along. You'll also want to turn the pumpkin (gently!) every couple of weeks so it doesn't get flat on one side.
3. Feed Regularly
Side dress your pumpkin vines every other week with a good, one inch layer of compost. In addition, look for any places along the vine where it may have rooted into the soil and give those spots a bit of compost as well.
4. Pinch Back New Growth
Once you have one or two nice pumpkins forming on a vine, pinch back the growing tip. This will direct the plant's energy into growing larger fruit rather than trying to put on more green growth and blossoms.
5. Remove Late Blossoms
You'll also want to remove any blossoms that appear after you've got a couple of good pumpkins on your vine to ensure that the plant puts its energy toward the fruit that is already growing, rather than trying to form new fruit.