How to Pollinate Squash When it Won’t Fruit

Growing squash was one of the most difficult plants for me as a beginning gardener. I found myself becoming frustrated over the process, as I could never manage to get any fruits off the huge squash vines throughout the season.

However, as I have gained more experience through the years, I’ve figured out some of the solutions to the biggest issues that I was having with these plants. Through this troubleshooting guide, we will go through the basics on squash care, identifying and solving common problems with growing this plant, and how to pollinate squash when it won’t fruit.

A beautiful male squash flower blossom, filled with pollen ready to fertilize! 

How to Care for Squash Plants

To approach a problem effectively, we must first know more about it on a foundational level. Summer and winter squash are among the most popular plants to grow in the garden. After all, it’s tough to beat fresh zucchini, butternut squash, and Jack-Be-Littles on a warm summer evening.

However, these plants can be tricky for us to grow. Many of us have experienced the frustration of nurturing a beautiful, leafy squash plant that makes tons of flowers but won’t produce any fruits from them. To fix this, we first have to look at the roots of the issue.

Squash are typically vining plants that produce large flowers. These flowers need pollen from the squash plant to produce fruit. They are full sun crops, and will thrive with six to eight hours of sun per day.

Squash, unlike other plants like tomatoes, do not have perfect flowers. A perfect flower is one that possesses both male and female reproductive parts in the same blossom. These types of plant flowers pollinate themselves easily, as all it takes for pollination is the male parts to drop pollen on to the female parts.

With squash plants, we don’t have this luxury. They produce the two types of flowers separately, with each being male or female. The first step to learning how to pollinate squash when it won’t fruit is finding the visual difference between the two.

Male flowers are typically elongated, with nothing but a stem and a flower head protruding from the vine. Female flowers, on the other hand, are typically shorter and have what looks like a baby squash attached where the stem of the male flowers would be.

Above shows a young male flower. You can tell this one is a male by the lack of the “baby squash” appendage that is seen with females. 

The picture above shows a pretty female flower blossom in early development. We can tell it is a female due to the extra bit of mass below the flower that looks like a tiny squash fruit. 

The pollen from the male flower needs to come into contact with the female flower in order to make fruit. Because of this, pollination is impossible without both sets of flowers.

For more information on squash plant care, check out this great video!

Now that we’ve decoded the difference between male and female flowers, let’s look at some common issues that you may be running into while growing squash.

Identifying Problems with Squash Plants

Squash can face a host of issues throughout the growing season that can prevent it from producing fruits. To begin, we’ll start at the most simple issue: a lack of female flowers on your plants!

You’ve looked at your squash plant, and found that you only see male flower heads on it. What can you do about this? This is very common, but don’t worry, it’s an easy fix!

Squash plants tend to put out more male flowers than females. The male flowers don’t take as many resources from the plant to create, so you will usually get three to four times as many males as females.

To promote more female flowers to form, simply remove some male flowers from the squash plant. This will signal the plant to increase flower production, and naturally, more female flowers will pop up over time! Make sure not to remove every male flower, though, as you still need some for your pollen.

A newly fertilized Birdhouse Gourd squash, with a male flower above it. 

Another issue that can prevent female flowers from growing is an absence of sunlight. Squash plants need full sun to grow, so a bare minimum of six hours will be necessary for your squash to produce.

Squash flowers require energy from the plant to be produced. Female flowers need much more energy to make, since they have more physical mass and intricate reproductive elements than male flowers.

If your squash plant isn’t getting enough sun, it can cause the plant to push out male flowers exclusively. Increasing the amount of light your plant gets can help with female production!

Nutrient deficiencies can also be the culprit in your lack of squash fruit fertilization. When a squash plant doesn’t have enough nitrogen or phosphorus, it will have a really difficult time producing female flowers.

To fertilize effectively, I suggest using a nitrogen-heavy product at the beginning of the plant’s life to build strong, healthy foliage. Once developed, switch over to a phosphorus-heavy fertilizer to promote flower production.

Lastly, an often overlooked component of pollinating your squash that we can forget about is the insects that do the pollinating! Beneficial bugs, like bees, are an essential piece of the equation for natural pollination of all of our garden crops.

Try planting other flowering plants, like hyssop or sunflowers, to promote more beneficial insects to your garden. No matter what, adding these plants will always make your garden more productive and lively!

Now that we’ve reviewed some of the common problems that could be preventing your squash plants from producing female flowers or pollinating, let’s look at some common pest and disease issues that you may be running into!

Common Pests and Disease for Squash Plants

When you begin your squash growing journey, there are some disease and pest issues that could be preventing your squash from pollinating and making fruit. Let’s identify these and find a solution!

-Powdery Mildew: A common issue in the garden, powdery mildew is a fungal infection that affects our plant’s leaves. This illness is characterized by white, powdery spots forming on the leaves of your plant. It can hurt flower production due to the leaves becoming sick and compromised overall.

-Methods to Fix Powdery Mildew: Prevention! A way to stop powdery mildew from ever becoming an issue is to be careful while watering. Make sure not to get the leaves wet, and if they do get splashed try to dry them off!

If the disease has already begun, watchful waiting is the best way to go forth. If you see powdery mildew affecting a couple of leaves, simply remove them so it doesn’t spread. Once the powdery mildew spreads to about fifty percent of the plant, it’s time to use more interventionary measures.

Try applying a solution of water, baking soda, and dish soap to the leaves. Mix 1 gallon, 1 tablespoon of baking soda, and 1 drop of dish soap together and spray on leaves once every other day until the mildew clears up.

Mosaic Virus: A rather nasty illness for squash of all types, the mosaic virus can cause your plants a lot of issues for flowering and making fruit. The virus presents itself as an arrangement of yellow spots on the leaves, which somewhat resemble a mosaic shape. Typically, mosaic virus spreads from contaminated tools or aphids carrying the disease.

How to Fix Mosaic Virus: Unfortunately, there is no cure for a plant already infected with mosaic, or any other type of virus for that matter. However, there is plenty that can be done to prevent the virus from taking a foothold in your squash patch.

If you find a plant with mosaic virus characteristics, quickly remove the entire plant from the ground and throw it into the trash. While this is painful, the goal is to keep the virus contained to the one plant and stop it from spreading to neighboring crops. Make sure not to compost the diseased leaves, either.

Also, limiting disease spreading bugs like aphids and others in the garden will decrease the chance of mosaic ever entering your garden in the first place. To do this, simply plant flowers that attract beneficial insects to naturally fend off these problematic critters.

Next, let’s examine a common pest that can ruin your squash harvest.

-Squash Vine Borers: The bane of squash plants, the horrible borer insect is a parasitic worm that bores into the stem of squash plants and eats away at it from the inside. They are identifiable by a yellow, pus-like material being visible at the base of the plant.

-How to Prevent Squash Vine Borers: There are two methods that I’ve had success with in dealing with these bugs in the past. Crop rotation, which means you grow your plants in a different place each season, helps stop the worms from developing in the soil and killing your plants.

This is because the squash borer moths will lay their larvae in the ground where they sense a squash plant, and next season will hatch and feast on your plants.

Another method that can prevent squash vine borers is using mulch to protect the base of the squash vines. When you mulch a squash plant heavily, the vine borers have a harder time pushing their way out of the soil and establishing in your squash vines.

While pests and disease can sometimes feel like an uphill battle, these interventions should help with prevention and treatment for squash disease.

Now that we have looked into some of the common pests and diseases in the garden, let’s break into the best solutions on how to pollinate squash plants when they won’t fruit.

How to Pollinate Squash When it Won’t Fruit

Okay, so you’ve applied the methods described in this article to your squash plant, and are still having trouble producing big, beautiful squash plants from your garden. I’m going to give you my foolproof pro-tip on how to force your squash to pollinate every time, without fail.

To backpedal a bit, earlier in the article we discussed a method of removing some male flowers on your squash plant to encourage your crop to produce more female flowers. Remember, these male flowers are carrying the pollen needed to pollinate the female flowers.

After you cut them from the plant, take them inside and lay them on a flat surface. What we are going to do is harvest the pollen from them and store it for when we spot a female flower on the plant.

All we are going to do is rub the cotton end of a Q-Tip into the bottom part of the male flower. After doing this for a few moments, you should see a yellow substance collecting on the cotton. This is the precious pollen we need for pollination.

Continue to collect pollen until your Q-Tip is visibly saturated with squash pollen. Place the Q-Tip in a zip lock bag, and store in the freezer until you spot a female flower on your squash plant. Once you see a female flower opening, simply rub the end of the Q-Tip with the pollen on the bottom part of the female flower and you are done!

Try to rub the pollen into the female flower as soon as you see the flower blossoming. You’ll have approximately twenty-four hours to do this part of the process before the flower closes and pollination for your squash plant ends.

The Q-Tip above is covered in pollen from our male squash flowers. This is more than enough pollen for fertilization! 

Bottom Line

Squash can prove a tough crop to grow initially. I know I had my own issues with producing anything more than leaves, stems, and flowers during my first few attempts. Just remember to…

-Identify your male and female flowers

-Monitor for pests, disease, and nutrient deficiencies

-Hand pollinate with the Q-Tip extraction method to guarantee pollination

If you can check the three boxes above, your growing pains with pollinating your squash when it won’t fruit will become history! As always, good luck in the garden and enjoy your lovely squash plants. See you next time!