Squash Sex: How to Hand Pollinate Squash to Prevent End Rot & Increase Yields

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. Then pop over to our Zucchini and Summer Squash Grow Guide for even more tips.

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. You can also use the same method to hand pollinate cucumbers and melons.

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…

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, usually within a few weeks! Hang tight.

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!