Why Aren’t My Pumpkins Fruiting?

Why Aren’t My Pumpkins Fruiting

“How do I get my Pumpkins to get past just flowering?” Question from Marilyn of Roseburg, Oregon

Answer: I am sorry to hear that your pumpkins are not producing! There are lots of things that could keep your pumpkins from setting fruit. Let’s start with what pumpkin vines need to grow and produce fruit.

What Pumpkins Need to Fruit

  1. Full sun (8 hours per day or more)
  2. Fertile, well-drained soil
  3. Regular water
  4. Fertilization with an all-purpose vegetable fertilizer
  5. Space–Vines require plenty of space to grow and branch.
  6. Time–Check the days to harvest for your pumpkin variety. If it is 100 days or more, then it is a late producer and just needs more time.

What Keeps Pumpkins from Fruiting

  1. Lack of female flowers (see below)
  2. Lack of pollinators–Bees pollinate pumpkin flowers, which is essential for them to fruit.
  3. Excessive heat– Very hot days (above 95 degrees F) and warm nights (above 75 degrees F) can stress vines to the point where they do not fruit.
  4. Too little light–Vines lack the energy to produce fruit.
  5. Too little time–If late-producing vines are planted too late in the season, they will not have enough time to fruit.
  6. Pests and disease–There are many pests and diseases that can reduce fruit output in pumpkins. If your vines look healthy, then don’t worry about this possibility.

Pumpkin Flowers and Fruiting

All squash, pumpkins included, have two flower types–male and female. Male blooms appear first on the vines as simple yellow flowers with stamens covered in yellow pollen. Female flowers develop towards the vine tips and have little fruits at the base of the yellow flowers as well as a single, central pistil in each bloom. If your vine has both flower types, then pollination failure could be the problem. Without pollination, developing fruits just shrivel. The solution is hand-pollination. Simply use a small brush to move pollen from a newly-opened male flower to a newly-opened female flower. It’s fast, easy, and will yield pumpkins.

It is quite possible that your vines are healthy and on the verge of producing. Time may be the only factor limiting their fruiting. Many late pumpkins will not start bearing until September. Keep me posted. I would love to hear the end of your pumpkin story.

Happy gardening

Jessie Keith

Black Gold Horticulturist


Click here to view my top 10 list of best-tasting pumpkins and winter squash!

Unproductive Pumpkins

“I’d like some info on why my pumpkin seeds didn’t produce pumpkins. There were lots of leaves and flowers, but no pumpkins. I planted them plenty early enough, and there wasn’t any frost. The leaves just started dying out by mid-September.” Question from Kimberly of Vancouver, Washington

Answer: Sorry to hear your pumpkin vines did not produce pumpkins! First, make sure that all of their growing requirements are met. Pumpkins need to be planted in spring, after the threat of frost has passed, for fall harvest. Full sun, summer warmth, and space (a 12’ x 12′ to 15 x 15’ patch) are essential for vining varieties. It pays to plant them on berms (click here to read all about berming) amended with lots of organic matter. Feed them with a fertilizer formulated for vegetables, and be sure they get plenty of moisture (probably not a problem in Vancouver).

If all their growing requirements were met, there are four more possible reasons why your pumpkins did not develop.

1. Lack of pollinators

Pumpkins have two flower types, male and female, and these are bee-pollinated. The male flowers are produced first, followed by the female blooms, which have small, underdeveloped pumpkins at the base of each flower. If you see female blooms on your plants, and no bees, this could be the problem. Without pollination, the developing fruits just shrivel and drop. If you think this is the cause of your troubles, try a hand-pollination method. Simply use a small brush to move pollen from a newly opened male flower to a newly opened female flower. It’s fast, easy, and will yield pumpkins!

2. Time

Lots of pumpkin varieties require good growing conditions for more than 100 days to produce. Early pumpkins are a good choice for those living further north. The varieties ‘Flatso‘ (85 days to harvest), ‘Chucky‘ (85 days to harvest), and ‘Cinnamon Girl‘ (85 days to harvest) are all early to produce.

3. Disease

Some fungal diseases and disorders will cause the fruit to shrivel up at various stages of development if you don’t think pollinators are your problem. (Click here to read a great article from Purdue University about pumpkin diseases and solutions.)

4. Squash Vine Borers

These pests bore into the stems of pumpkins and other squash and cause whole vines to die back because they are cut off their water. Usually, with vining pumpkins, some of the vines survive because they root along the ground and survive, so this is often less of a problem. Nonetheless, click here to read a great Q&A about squash vine borers to determine if this is your problem.

Better luck with your pumpkins next year!

Jessie Keith

Black Gold Horticulturist

Fun Fall Decorating with Pumpkins

This elaborate collection of pumpkins and gourds annually graces Lisa and Jeff Tice’s home in Greenville, SC. (Photo by Marian St Clair)

Once upon a time, pumpkins only appeared briefly as round, orange Jack-o’-lanterns for Halloween night, as the tasty main ingredient in a traditional pie at Thanksgiving, or were mentioned in passing as a potential means of transportation and affordable housing in children’s fairy tales. Today, however, pumpkins have quickly transformed into the hottest decorating item for fall.

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This colorful pumpkin planter is the creation of Marian St Clair of Greenville, SC. (Photo by Marian St Clair)

Not bad for a native New World fruit (no, a pumpkin isn’t a vegetable). Pumpkins, Cucurbita pepo, and C. maxima, are members of the squash family, which includes juicy cucumbers, loofah sponges, tough-skinned winter squash, and gourds.

Carved Pumpkins

The reason for the pumpkin’s surge in popularity is its good looks and long durability, potentially lasting weeks in outdoor arrangements thanks to its colorful hardened outer skin – if it has been cured correctly. This amazing resilience, plus the wide variety of sizes, shapes, and colors now being grown for both crafters and foodies, provides homeowners and professional designers with quite a bit of inspiration.

For those who love the time-honored ritual of carving a pumpkin, there are carving kits complete with specific tools and traceable patterns, and many how-to videos will help you create something more dramatic than the simple triangular eyes and noses of the grinning jack-o’-lanterns of yesterday.

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Master pumpkin carvers display their amazing skills at the North Carolina State Fair in Raleigh, NC each October.

Painted Pumpkins

If you have a really steady hand, a pale three-dimensional face can be artistically carved into a pumpkin. Though removing the outer skin may cause the pumpkin to deteriorate more quickly, the inner flesh is firm enough to hold up for several days to a week if outdoor temperatures are cool and you keep your work of art out of direct sunlight. Part of the fun, however, may be watching your sculpture transform into something really ghoulish as it disintegrates.

Painting pumpkins has become a recent popular trend. You can spray paint them solid black, white, or even gild them in gold, silver, and bronze to match your other porch embellishment. Stenciling designs, university logos, and your house numbers with acrylic paint onto a pumpkin should last awhile, as the pumpkin’s outer shell hasn’t been compromised. Having your children or grandchildren paint faces on several smaller pumpkins, rather than carve them, is another great way to enjoy their precious creations a little longer, too.

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Small painted pumpkin faces for sale at the North Carolina State Farmer’s Market in Raleigh, NC.

Small painted pumpkin faces for sale at the North Carolina State Farmer’s Market in Raleigh, NC. Pumpkins can also be utilized as containers. Cutting off the top, then scooping out the seeds and most of the inner flesh provides a temporary seasonal pot for mums and pansies. Remember that if you plant directly into the fruit, moisture in the potting medium could cause the pumpkin to rot quickly; but, if you simply set an already potted plant into the open shell, it may hold up better.

Choosing Varieties

Since there are so many varieties of pumpkins on the market, grouping them in natural arrangements is another way to showcase your front door for fall. Whether you simply line pumpkins up the stairs or assemble them around your threshold, their size, shape, and color will certainly make a spectacular statement.

The giant pumpkins at the North Carolina State Fair in Raleigh, NC are worthy of becoming Cinderella’s coach. (Photo by Celeste Sagi)

For more inspiration, visit your local farmer’s markets, botanical gardens, and zoos where grand displays of pumpkins are popping up everywhere. If you want to try your hand at growing your own pumpkins for next fall, here are a few growing tips:

Growing Pumpkins

Pumpkins need a long growing season, often requiring over 100 growing days to transform from flattened seed to fully mature vines, producing thick-skinned fruits to cut for display.

They also require full, direct sun, and they need lots of room to sprawl, with vines easily covering an area 20-feet across. Pumpkins don’t like cold soil, so direct plant seed once the soil temps are closer to 70-75 degrees F.

Starting seed indoors can be tricky, as pumpkin seed germinates quickly and seedlings get leggy fast, so they are difficult to transplant with success.

The reasons pumpkins are traditionally planted on a hill is that mounded soil heats up quickly and drains well. Black Gold® Garden Soil would be a good choice for creating these raised planting areas in the home garden.

Pumpkins are greedy feeders, needing additional fertilizer and supplemental watering in droughty summers. Here is another reason why incorporating Black Gold® Garden Soil into the planting area would provide essential organic matter to hold moisture, while at the same time helping feed these hungry plants for up to six months.

When watering your pumpkin patch, try to keep water off of the foliage to help prevent foliar diseases, instead deliver it down to the roots where it is needed. Soaker hoses are perfect for this.

Harvesting Pumpkins

The deep color change is a pretty good indicator that your pumpkins are getting ready to harvest. Another indicator is that their supporting vines begin to turn brown, but the best test is when you can no longer easily puncture the outer skin of a pumpkin with your fingernail. (Some pumpkins are more soft-skinned, but overall this is a good test.)

You may find that you are developing impatience to pick and enjoy your pumpkin crop, feeling much like Linus waiting for the Great Pumpkin in the Peanuts comic strip, but resist the temptation to cut them too early. Pumpkins last much longer when harvested after they are fully mature. Then you will be able to enjoy them longer for all of your fall decorating needs.