Growing pumpkin plant flowers but no fruit is seriously disappointing. Huge green leaves and yellow flowers have such promise, yet there are no pumpkins to be seen. There are a number of reasons why this happens. The most likely is that you have male flowers, or your female flowers aren’t being pollinated. Heat, drought, and the wrong soil conditions can also be the reason you’re not seeing bright orange pumpkins on your vines. Fortunately, there are ways to help your pumpkin plants produce fruit. The first step is figuring out why your plants don’t have pumpkins yet.
- Male vs female pumpkin flowers
- Pollination of pumpkin plant flowers but no fruit
- Hand pollinating pumpkin flowers
- Why do I have pumpkin flowers but no fruit?
- Temperature levels growing pumpkin flowers but no fruit
- Pumpkin flowers but no fruit from wet soil
- Nitrogen levels can mean pumpkin flowers but no fruit
Why Do I Have Pumpkin Plant Flowers But No Fruit?
If your pumpkin plants have flowers but no fruit, it could be that you have only male blooms, which appear up to two weeks before the female flowers. Pumpkin plants need both male and female blooms in order to pollinate and bear fruit.
If this is your first time growing pumpkins, and it’s early in the season, don’t stress yet. Its normal for vines to have a flush of male flowers first, and for female ones to come later. But later in the year, there is probably something else going on.
What’s the Difference Between Male and Female Pumpkin Flowers?
Female flowers have an ovary, which appears as a slight bump or nodule on the stem just behind the petals. The male blooms appear about six to eight weeks into the pumpkin’s growth cycle. These flowers are tall and stick straight up, whereas female flowers grow closer to the vine and lower to the ground.
Male flowers have the job of alerting bees that they have pollen and nectar, so when female flowers appear 10 to 14 days later, the bees will know where to get food. As the bees fly from flower to flower, pollen is transferred from the male to the female flowers, resulting in fertilized female blooms that develop the pumpkin fruit.
How Can I Tell If My Female Pumpkin Flowers are Pollinated?
If you suspect that your female pumpkin flowers aren’t getting pollinated, the best way to check is by observing the activity in your garden. Morning is when the blossoms open and the perfect time to sit and keep an eye out for pollinators. If you see bees going from flower to flower, the odds are good that the plants are pollinated.
You can also look closely at the female flowers to see if pollen is sticking to the plant’s stigmas. If the blossoms are wilting, it’s a good sign that the female flowers have been pollinated. If you don’t see any bees visiting your pumpkin flowers, your best option is to hand-pollinate.
How Do I Hand-Pollinate Female Pumpkin Flowers?
Pollination occurs when a bee collects pollen from a male flower and transfers it to the female flower. So, if you aren’t getting any bees visiting your garden, you’re not going to get any pumpkins. You can attract bees by growing plants like lavender, bee balm, echinacea, and certain wildflowers. But if you want to ensure pollination, the best way is to do it yourself.
There are two ways to hand pollinate. The first method is to use a fine paintbrush to pick up pollen from the stamen of a male flower and touch it to the female flower’s stigma at the center of the bloom.
The other way to hand-pollinate is to break off the male flower and shake the pollen-filled stamen over the stigma.
Pumpkin Plant Flowers But No Fruit Late In The Season
If lack of pollination is not the problem, other factors could be causing your pumpkin production problem.
It’s Too Hot and Dry
Too much heat could be another reason your plants aren’t generating fruit. Pumpkins thrive in direct sun, but if the weather is too hot and humid, it can interrupt the production of female flowers. If the plant is stressed, it won’t have the resources to make fruit.
High temperatures and drought conditions can also prevent pollen from germinating and fertilizing the female flower. Pumpkins require a lot of water to remain healthy. During a heatwave, ensure you’re providing adequate irrigation and add mulch around the base of your plant to retain moisture and cool the roots.
It’s Too Wet
Pumpkins need lots of water, but too much moisture can stress the roots and stop the plant from producing female flowers. Whether it’s from too much rain, overwatering, or poor drainage, waterlogged roots can result in root rot and kill not only the fruit but also the entire plant. If there’s excessive rain in the forecast, you can protect your pumpkin plants by covering them in plastic until the deluge is over.
Too Much Nitrogen
If there are bees in your yard, the weather conditions are good, and your pumpkin plants still aren’t producing fruit, the problem could be too much nitrogen. If your plant has lots of leaves and no flowers or only has male flowers and yellowing or brown leaves, it’s a sign that the nitrogen content in the soil is too high.
While pumpkin plants need nitrogen-heavy fertilizer in the early growing stages to produce a healthy plant, too much nitrogen can stop female flower production. Stop giving the plant nitrogen six to eight weeks after planting and switch to a phosphorus-heavy fertilizer once the flowers start to appear to spur bloom production. Once the fruit starts developing, use a potassium-rich fertilizer for big, healthy pumpkins.
Why Do I Have Pumpkin Plant Flowers but No Fruit
As you can see, there are several reasons your pumpkin plant could be flowering without producing fruit. If it’s early in the growing season, be patient. It could be that these flowers are male, and the female blooms will appear in a week or two.
If you’ve identified both male and female flowers, and there’s still no fruit, lack of pollination is the most likely cause. If you aren’t attracting bees to your plants, you’re not going to get pumpkins. However, excessive heat, too much water, or using the wrong fertilizer could also be the problem.