How to pollinate zucchini?

Why didn’t my squash plant have any squashes?

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When I think of zucchini, I think of abundance. You plant one zucchini plant and it produces so much fruit, that you end up giving it away to family, friends and all your neighbours.

Thanks to changing climatic conditions and a lack of pollinators, zucchini plants aren’t producing as prolifically as they once did.

What does zucchini need in order to produce lots of fruit? Sunshine, heat and regular pollination.

Zucchini is not self-pollinating. It has male and female flowers that require the assistance of bees and bumblebees to fly from male flowers, collect pollen, then disperse the pollen to the pistils of female flowers.

What doesn’t zucchini need? Cool temperatures, persistent rain and absent pollinators.

Unfortunately in today’s conditions, if you’re looking for a bumper zucchini crop, you’ll need to step in and carry out the pollinator’s role.

Watch this video, where I show you how to easily hand pollinate your zucchini plants, in order to have a much larger harvest. All you need is a paintbrush!

Happy Gardening!


Giving Your Zucchini Plants A Nudge With Hand Pollination

If you’re growing zucchini in your garden this year, you best be armed with a plethora of recipes that call for the vegetable. Believe it or not, a single zucchini plant can produce up to 10 pounds of zucchini in one growing season. Yikes! I have four plants…that’s right, four. I have myself and a lack of research to blame for that.

Luckily, there are so many ways to eat it; from soups and stir-frys to grilling on the BBQ, zucchini bread, and even chocolate cake! Zucchini also freezes well for the winter if grated in advance. I personally love adding shredded zucchini to any kind of ground beef mixture I make. It’s a good way to cut down on beef and get more veggies into your diet. I better make room in the freezer!

It’s amazing how quickly zucchini plants start bearing fruit. Last week, we had a heat wave that lasted a week where I live. The “greenhouse effect” was super beneficial to my gardens; all of a sudden my zucchini, pepper, and bean plants tripled in size. Within days, big, beautiful blooms appeared on the zucchini plants, which meant the magic was about to happen! Sure enough, a couple of days after that, my first two zucchini appeared.

Fun fact about zucchini plants: they actually have both male and female flowers, which also happen to be edible! Eaten raw, they’re crisp, fresh, and sweet-tasting. The female zucchini flowers have short stems and three parts called the pistil. For every female flower, there are usually about three male flowers. These are much larger than the females and have longer stems. Zucchinis depend heavily on bees to move the pollen from the male to female flowers. If the female flowers don’t receive enough pollen, the resulting zucchinis will likely be misshapen and may even shrivel and fall off.

I haven’t seen many bees in my gardens recently, and because the female flowers are only open for one day, I knew pollination had to happen quickly. Worried the bees would miss the window of opportunity, I decided to take matters into my own hands so that my zucchini crops thrive this summer.

The entire process was incredibly easy; all you need is a small paintbrush. Keep in mind that propagation has to happen first thing in the morning. All I did was dab some pollen from the male anther, which sits in the middle of the flower. The pollen rubs onto the brush very easily. Then, I carefully brushed the pollen onto the female stigma, which is inside the flower and is connected to the ovary. Sounds sexy, but I can assure you it’s not.

Don’t have a paintbrush lying around? No problem! You can also pollinate by taking the petals from the male flower and gently touching the male anther to the female stigma.

Beyond pollinating by hand, zucchini plants are actually incredibly low-maintenance. They grow well in most soils with very minimal care, and they’ll do well until the first frost kills them. You’ll get the best flavor if you pick your zucchini off the vine when it’s about 6 inches long. Keep in mind, the more you harvest, the more your plant will produce. If you find you’re inundated with zucchini and can’t possibly think of one more thing to make with it, then leave the squash on the vine to grow as big as possible. This should significantly slow your plant’s yield.

I have a feeling my four plants will be producing like crazy this summer, especially after giving them a nudge with pollination. Maybe it’s purely coincidence that within days of using the paintbrush technique I had two zucchinis appear, but I feel like it’s working already! Anyone who invites me over for dinner this summer will likely get a bottle of wine, and a basket of homegrown zucchini!

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Catherine Sherriffs

Editor at Garden Culture Magazine Catherine is a Canadian award-winning journalist who worked as a reporter and news anchor in Montreal’s radio and television scene for 10 years. A graduate of Concordia University, she left the hustle and bustle of the business after starting a family. Now, she’s the editor and a writer for Garden Culture Magazine while also enjoying being a mom to her two young kids. Her interests include great food, gardening, fitness, animals, and anything outdoors.Follow me

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Some vegetables are self-pollinating meaning they do not need the assistance of bees or other insects or the wind for pollination and the production of fruit.

Self-pollinating vegetables include tomatoes, green peppers and chili peppers, eggplants, green beans, lima beans, sweet peas, and peanuts.

Pollen is required for a flower to produce a fruit. Self-pollinating vegetables have what are called “perfect” or “complete” flowers because each individual flower contains both the male (anther) and female (stigma) flowering parts necessary for fertilization and fruit production. Pollen must pass from the anther to the stigma for fertilization to occur. Some vegetables—squash plants for example–produce separate male and female flowers—those flowers are not complete or “perfect.”

If self-pollinating vegetables are not producing fruits, you can help them along. When a self-pollinating plant is flowering you can simply give it a gentle shake or shimmy to help the pollen drop. You can also use a soft cotton cloth to fan the flowers—again helping the pollen to drop from the anther to the stigma.

Have you ever tried to grow squash, but then much to your dismay, the promising little squash rots and falls off instead of getting larger? Well… that is most likely due to a lack of pollination! But don’t worry! There is a very easy solution. It has to do with “the birds and the bees” ~ or a lack thereof!

If you hope to have big healthy zucchini this summer, read along to learn all about hand pollination! Let’s explore the difference between male and female flowers, and exactly why, when and how to hand pollinate your squash plants. Check out the video at the end of this post to watch me pollinate ours!

Many people wonder about the pattern on the leaves. No, that isn’t mildew or disease, though it does look similar! Many squash and melon varieties have a natural variegated leaf pattern. This Dunja zucchini is actually naturally resistant to powdery mildew! Mildew will usually look a little less uniform, more raised and fuzzy, and start on the underside of the leaves first.

Why Hand Pollinate Squash?

When a female squash blossom goes unpollinated, the small attached fruit will fail to thrive and develop. It will stay stunted, start to rot from the flower end, and eventually die and fall off. Therefore, if you want to ensure your plants produce edible fruit for you to enjoy, hand pollination can vastly increase their success – and your yields!

This idea applies to summer squash, like zucchini or crookneck squash, as well as winter squash like butternut, pumpkins, or acorn squash.

If you live in a place that has a robust, healthy bee population, you may not find the need to do this. Unfortunately, that is not the case in most places. Even here in our garden, which is bursting with pollinator-friendly plants and buzzing with bees, we find that some squash still fall off due to lack of pollination on occasion! So I still routinely hand-pollinate. I mean, why not guarantee success?

For a list of plants that will help attract pollinators to your garden check out our “Top 23 Plants for Pollinators” article!

Male vs Female Squash Blossoms

The first thing you need to know if you want to hand pollinate squash is how to tell the difference between the male and female flowers. And, each of their roles in pollination and fruit development! As with many things in this world, both a male and female are needed to create new life.

A female squash blossom is most easily identified by the little immature squash fruit that is attached at the base of the flower. Additionally, if you peek inside the flower, the inner bits are more round and curvaceous. That is called her stigma.

On the contrary, a male squash blossom lacks any sort of fruit. Instead, it has a straight plain stem at the end of the flower. Inside is his anther – an appendage with a pollen-covered tip. See the images below.

How to Hand Pollinate Squash

In order to hand-pollinate squash, all you need to do is transfer some pollen from the male flower’s anther onto the female flower’s stigma. It is really as easy as that! Let’s go over a few pointers though.

You can use a few different methods to transfer the pollen from the male to female flower. Some folks rip off the male flower entirely, peel back its petals, and rub the anther directly on the female stigma. I personally don’t love this method… I prefer to leave the blossom in place for the bees, or for later use! Others use a Q-tip. In my experience, a lot of the pollen sticks to the Q-tip itself, leading to less pollen transferring from flower to flower.

This leads us to my favorite method: using a dainty paint brush! I simply collect some pollen from the male, spread some onto the female stigma (or many ladies), and it’s done! Using a paintbrush is really effective, but also feels fun and fancy! Note that I typically use a smaller paintbrush to hand pollinate than what is shown in the video and photos. I can’t currently find my go-to brush…

Collect pollen from the male, and deposit it on the female. Boom! Done.

Once the pollen has been transferred to the lady bloom, she will be happy. The immature squash will now grow big and strong! Remember, bigger isn’t always better – especially in the zucchini world! We prefer to harvest our squash at a nice medium size. When squash are allowed to grow too large, they become more tough, pithy, and seedy.

When to Hand Pollinate Squash

Give them some love as soon as they open! And by love, I mean pollen of course.

I have found that most of our squash blossoms open in the morning, and close up by the evening, so checking daily is important if you want to get to them all. However, sometimes they can open at various times of day, so morning isn’t necessarily a steadfast guarantee. If you miss the initial bloom – don’t fret! You can usually carefully peel open blooms that have already opened and closed to access their insides for a couple days after. This goes for both males and female flowers, which is just one more reason to not pick off the males!

Speaking of males and females… I often hear of people experiencing frustration because they have only male flowers, or only female flowers, and not both at the same time. Early in the season, some squash plants do produce one or the other more heavily. They will even out and catch up as the plant matures! Hang tight.

Four days after being hand pollinated. The squash is growing quickly!

To help ensure there will be a good mix of male and female flowers open around the same time, we always grow several squash plants! Did you know you can use the pollen from one squash plant to pollinate the female on another plant, even if they’re a different variety? Yep. You sure can!

Cross-Pollinating Squash

Are your squash plant is coming up short, with either male or female flowers lacking? The good news is: any summer squash male can be used to pollinate a female bloom of a different variety within the summer squash family! For example, you can use a crookneck or yellow squash male to pollinate a green zucchini female. Furthermore, this rings true for the winter or hard squash family too! Pumpkins, butternut, acorn, spaghetti squash, or similar can be used to hand pollinate one another.

Truth be told, in a pinch – any squash can technically cross-pollinate any other squash, regardless if it is a summer or winter variety. They’re all the same species! However, I have heard you get the best fruit development by using summer types for summer types, and winter for winter.

After cross-pollination, the resulting squash fruit will still develop into the designated variety of the mother plant. However, you will likely have issues if you attempt to seed-save from that fruit to grow more in the future. The next generation will not breed true due to the cross pollination that occurred. The fruit that grows from those saved seeds will result in something is different from either of the parent plants.

However, keep in mind that bees will naturally cross-pollinate the squash plants in your garden too! The only way to prevent that is to grow only one variety of squash in a controlled environment. Most home gardeners I know like to plant more than one variety of squash!

We are perfectly okay with this scenario. Instead of attempting to seed-save squash, we simply buy more new seeds every few years. Yes, you can successfully grow plants from seeds that are past their “best by” date! Just sow a few extra as they age. Plus, getting fresh seed enables us to try new varieties. Therein lies the beauty of gardening – trying new things!

So, are you ready to try your hand at pollinating squash?

Here is a video of the very quick-and-easy process. Don’t mind my sense of humor.

It is really THAT simple.

And now you’re off! Go hunt down some squash flowers and help them have sex. May you be blessed with plenty of healthy zucchini this summer. If you find yourself with some large overgrown squash, you should try our Fiesta-Style Stuffed Squash recipe! Loaded with wild rice, black beans, veggies, flavor, and protein… you can’t go wrong.

I hope you found this helpful! Please feel free to ask questions, and spread the squash sex lovin’ by sharing this post!

How To Hand Pollinate Squash for a Larger Yield

Have you ever noticed baby squash on your plant at the beginning of the season? It’s an exciting moment, knowing within a short period of time you’re going to have a healthy squash to eat. So it can be disappointing when that same baby squash shrivels up within a couple days. What happened? The plant looked healthy. This issue you just stumbled upon was no fault of your own, but you can help prevent it! Your squash simply wasn’t pollinated. You can learn how to hand pollinate squash for a larger yield.

By handing pollinating your squash you can increase the yield that your plant produces. And it’s easy. Squash flowers are big and bright, making them hard to miss, and easy to pollinate.

Understanding Your Squash Plants

Squash is part of the Cucurbitaceae family (also referred to as the cucurbits family and gourd family). There are actually over 700 species. This family includes summer and winter squash, pumpkins, melons, cucumbers, and zucchini. This family is “monoecious” which means it has two different types of flowers it produces – male and female. This plays an important role when growing and harvesting your squash.

Squash Varieties

There are many squash varieties, both summer and winter squash. A few of my favorites summer squash include early prolific straight neck yellow squash, summer crookneck yellow squash, early white scallop pattypan Squash, cocozelle zucchini, black beauty zucchini, yellow zucchini, and round zucchini.

A few of my favorite winter squash include spaghetti squash, table king acorn squash, table queen acorn squash, Waltham butternut squash, and early butternut squash.

Female Flowers

There are two ways to identify a female flower on a squash plant. The first way is to look for fruit. The female flowers are the ones that will actually produce your squash. The female flowers of squash will have a small fruit at the base of the flower by the time the flower opens.

The other way to identify female flowers is by looking at the center of the flower. Female flowers will have a stigma in the center of the blossom. This is smooth and almost crown-shaped.

Male Flowers

There are also two ways to identify male flowers on a squash plant. Unlike female flowers, male flowers do not produce fruit. This means that the stems are just straight and skinny without any fruit showing. The center of the flower blossom is also unique for male flowers. Male flowers have anthers in the center of the blossom. These look like a tiny Popsicle dipped in pollen.

Why You Should Hand Pollinate Squash

There are a few reasons why you may want to hand pollinate squash. It will ultimately come down to not having insects pollinating your squash for one reason or another. It can also be because you simply want to try to increase the yield you’re already getting.

Male and female flowers are opening at different times

Have you ever only had male flowers, or only female flowers, but not both? I have. The sex of the flower is actually influenced by the temperature, day length, and plant maturity. If you find you only have male flowers you can cut them and store them in the refrigerator for a few days.

The bees haven’t been stopping by

After Hurricane Irma, I noticed a drop in bees that lasted many months in my garden. Whether it’s nature, pesticides, or not having a pollinator-friendly garden, sometimes you may run into the issue of just not having enough pollinators in your garden.

I do recommend if you have a vegetable garden to also have some flowers as well. Milkweed is well known to be attractive to monarch butterflies. I also notice zinnias and Mexican heather attract bees and butterflies to my garden. I recommend going to a nursery or other garden center and taking a walk around. Which flowers have the bees been flying around and pollinating? Those are the ones you may be interested in getting. That’s how I first discovered Mexican heather, and we’ve been friends ever since.

You’ve built a squash enclosure to keep out the vine borers

This is actually the main reason why I started to hand pollinate squash. If you live where there are squash vine borers you may know what I’m talking about. Your squash plants are bushy and healthy, things are going great. And then one day you go out to check on your plant, and overnight, your plant has died. The stems and leaves are limp and hanging. And if you look closer you’ll notice there’s a hole, or two, or three, by the base of the plant. Enter the squash vine borer.

I don’t even bother trying to spray my plants with anything organic. These vine borers literally bore into the stem, and they’re protected inside the stems of the plants. The best way I have found to prevent vine borers as an organic gardener is to keep my plants physically protected at all times (check out what I use). This can be accomplished by growing under a row cover. Any sort of enclosure using a shade cloth will work. But by doing so, you will also keep beneficial pollinators like bees away from your squash. The solution, of course, is hand pollinating squash.

Hand pollinating is super easy and there are a few different ways you can go about it. Keep in mind, whichever of the following methods you use, you’ll want to hand pollinate squash in the morning. Squash blossoms open in the mornings, so that’s when you’ll want to pollinate them. You can also note that one male flower can be used to pollinate several female flowers, so it doesn’t need to be a 1 to 1 ratio. And by all means, feel free to wear your bee hat 😉

Method 1 to Hand Pollinate Squash

This first method only requires a scissor. First, you’ll want to identify which are your male follows and snip them, leaving some of the stems to hold onto. If you cut off a female flower there’s nothing you can do. It happens. I was once trimming my beautiful butternut squash vine and accidentally clipped the vine that the butternut squash was attached to. Moving on…

Once you have your male flower you’ll now want to use it sort of as a paintbrush and rub it against the center of the female flowers. Make sure the pollen from the male flower is getting on the stigma. You may find you need to remove the petals of the male flower to do this.

And that’s it! You’ve hand pollinated your squash 🙂

Method 2 to Hand Pollinate Squash

This method is really just an extension of the first method. If you find you only have male flowers, and no female flowers, you can clip your male flowers and hold onto them for a few days. You’ll want to remove the petals and store your flowers on a slightly wet paper towel in your refrigerator. Be sure the pollen isn’t touching the paper towel – we want to keep this dry. You can store them in the refrigerator for a few days. I recommend going outside each morning and checking to see if any female flowers have opened.

Method 3 to Hand Pollinate Squash

This is my personal favorite method and one that I use. I prefer this method over the others for a couple reasons. One, I prefer it aesthetically because it doesn’t require cutting off the male flowers. Two, if I want I can still use the male blossoms to eat. That’s right – bake them, fry them, stuff them, or add them to soup or pasta.

For this method you’re not cutting off the male flowers, you’re just moving the pollen from Point A to Point B. To do this you can use a paintbrush, a makeup brush, even a Q-tip. Whatever you use, you’ll want it to be dry. Then you’ll brush it against the center of your male flowers to collect the pollen. Once you’ve collected your pollen, carefully move your bush to the female flower and “paint on” the pollen to the stigma.

You are now a certified honey bee. I hope you enjoy the fruits of your labor and now know how easy it is to hand pollinate your squash. Do you hand pollinate your squash? What’s your favorite variety? Comment Below!

Hand Pollinating Squash

Jay White, Horticulture Graduate Student, Texas A&M University

Squash vine borers are just horrible in my part of Texas. Because of this, it is almost impossible to get a great crop of any of the standard summer squash varieties grown in our area (yellow crookneck, zucchini or patty pan).

Squash Vine Borer Moth in Patty Leander’s garden. Photo by Bruce Leander

As I talk to people, I get more questions about how to control this destructive little pest than any other. Quite frankly, if you are an organic grower, there is not much you can do to beat the borer besides growing your plants under row cover (if you are not organic, Sevin dust does a fairly decent job of keeping borers away, but it needs to be applied every four or five days). If you properly grow under row cover you will definitely stop the vine borer. However, you will also prevent bees and other pollinators from reaching the plants. Because of this, if you want any fruit, you will be forced to pollinate your plants by hand. Luckily, hand pollination of squash plants is very easy to do.

Female acorn squash on trellis

Flower Identification – Hand pollination of squash blossoms requires no special skills or tools. All you have to do is be able to identify male and female flowers. On squash, this is very easy to do. Female flowers will always have a tiny fruit under the flower.

Closeup of female stigma
Back of female flower

Male flowers grow on a long narrow stem. You can also tell the two apart by looking at the reproductive organs found in the center of the flower. The female flowers contain the stigma. The stigma generally looks like a flower in its own right. It has several “bumpy structures” that cluster around a central opening. Anthers (male parts) look a lot like the thing my wife uses to apply eye shadow.

Front of male flower
Back of male flower

Hand Pollination – When growing under row cover you will need to pollinate as soon as the flowers begin to open. When this happens, roll back your cover and find a male flower. Cut it off where the flower stem meets the main stem of the plant. Next, gently remove all of the petals from the flower. Once the petals are gone you are left with a stem and exposed anther that is about 4″ to 6″ long.

Anther ready for pollination use

Now find a female flower and use your stem and anther to “paint” the stigma in the center of the female flower. Gently rub the anther over the stigma a few times. Then go on to the next female flower. Each anther can be used to pollinate approximately five flowers.

“Painting” the stigma

Caution – A fellow gardener once told me that they were crushed to find a vine borer trapped under their row cover after they had hand pollinated. If this happens to you don’t worry. While it is best if you can keep your squash plant bug free for its entire life, a mature squash plant can usually “outgrow” a worms infestation if the eggs are not laid until after pollination occurs. Because of this, many gardeners that grow under cover often remove the cover completely when the pollination is done.

If you want to keep the cover on throughout the life cycle, work with a buddy and pollinate in the late afternoon (borers are most active before noon). Roll back the cover and quickly harvest several male flowers. Put the cover back in place as you strip the petals from the male flowers. When you have all of the anthers exposed quickly pull the cover back and pollinate all of the female flowers at one time, then quickly put the cover back in place and anchor the sides to the soil.

Squash being grown under cover in Patty Leander’s garden. Photo by Bruce Leander

This method of hand pollination is a great tool to master and you can use it for all of your cucurbits. If you do it right, I am convinced it will increase your yields This fall I grew acorn squash. Since we have been short on bees, I did a small experiment. I hand pollinated half of my vines and let nature pollinate the other half. I got almost a 100% yield from the flowers I pollinated. Mother Nature was only successful about half the time.

This article originally appeared in the blog “The Masters of Horticulture” by Jay White

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