Growing Giant Pumpkins

Growing Giant Pumpkins

Growing GIANT Pumpkins

A Sunday Seminar at Hyannis Country Garden, Sunday March 29th, 2015

Looking for a coach for a princess with glass slippers? Need a place to stash unexpected or unwanted guests? Do you want to make a hundred pumpkin pies this Thanksgiving? You Can Grow That!

  • To produce a BIG pumpkin you’ll need to grow a BIG vine. This means you have to have the right seeds, the right soil, the right sunshine and the right amount of water.
  • How serious are you? Are you out for fun, and a few large pumpkins? Or are you the super competitive type who wants to win the grand prize at a state fair pumpkin contest?
  • Make sure you have a spot in FULL SUN: 6+ hours dead-on.
  • When possible, avoid windy, exposed site. Give them space…some growers say 50×50 foot area per plant if you’re going for a prize.
  • Prepare soil well using compost/composted manure spread thickly (3 to 4 inches) over an area about 5 feet in diameter.
  • Spread an organic fertilizer such as Plant-tone over the same area and turn the compost and fertilizer into the ground.
  • Start seeds indoors in late-April. Provide good light from a southern-facing window or gro-lights placed about 4” above the growing plants, 14 hours per day.
  • Don’t plant your seedlings too early! Night temperatures should be reliably above 50. Protect seedlings with floating row cover/harvest guard for the first two weeks to prevent sunburn and to hold warmth around plants. If the weather is windy, keep this covering on until the end of June. When planted, begin to keep soil evenly moist.
  • Water deeply less often – a deep soaking once a week for older plants is better than a little every day. Hand watering is fine for the first week or two, but after that use soaker hoses or sprinklers. If using sprinklers, water in the morning so that the foliage dries off quickly.
  • Mulch around plants as soon as they are put in the ground. This holds in moisture and helps prevent diseases. Mulch the garden to control weeds. Weeds rob water and nutrients from your plants!
  • Use a fungicide from the first week and spray under leaves, tops of leaves, and stems to help deter mildew. Green Cure, Actinovate, Serenade or a sulfur spray are all organic fungicides. Apply regularly according to directions.
  • Pumpkin roots root at each leaf node – this can supply a supplemental root system, which is good. But these roots can also be problematic when the big pumpkins start to form. Pull roots up and mulch under the stems in this region next to where developing pumpkins are forming.
  • As vines grow keep the plants evenly moist. Fertilize regularly – Neptune’s Harvest is a good foliage and soil fertilizer that’s organic. If you’re using a synthetic fertilizer, apply after watering well.
  • Your plant is a system…it’s a pumpkin producing factory. Each leaf produces the energy to make 4 lbs of weight on your pumpkin. Every leaf, stem, and root is working to put size on the fruit.
  • Choose the largest of the developing fruit and clip off the rest. (see point #2) If going for SIZE, only let one grow on.
  • Competitive growers don’t allow pollination until 150 to 200 leaves have grown! (see point #2) Probably impractical on Cape Cod.
  • If going for HUGE, only grow one per vine. This is for the truly obsessed, mind you. Once you settle on The One, clip the end of the vine so that the plant will put all energy into that fruit.
  • In hot, dry summers shade the fruit in August so that it doesn’t harden and stop growing.
  • To control shape, roll the pumpkin gently and slowly as it develops so that it doesn’t immediately flatten. Be careful not to tear the vine and know that this becomes impossible after awhile.
  • There are as many formulas for producing GIANT pumpkins as there are gardeners. Like all other aspects of the garden, there is no one right way. Remember these words: this is supposed to be fun!
  • your experiences with us! Send us photos by email or post your progress on our Facebook page.
Most pumpkins look large when Miss Maple is on top of them. These are normal-sized pumpkins, of course.
This truck was parked in front of Hyannis Country Garden one fall. We don’t know how they managed to lift this giant pumpkin into the truck bed, or how they are going to get it out!

Leave a Comment

Subscribe To Our Newsletter

Sign up for our weekly email about sales and events.