Squash and Cucumbers: All Flowers and No Fruit?

Winter squash flowering, but no fruit - yet! Copyright Jill HendersonJill Henderson Show Me Oz
It happens every year. The weather warms up, the rain comes at the right time, and the squash, cucumber and melon vines have finally taken off. At last, the small baby plants you’ve coddled all spring are literally sprawling all over the place and flowering for weeks now. Yet, not one single fruit is in sight. For years I went through the same thing – worrying and wondering what the heck I’d done wrong. Eventually, the fruit would come and I’d forget all about it.  But, it wasn’t until I started saving seed that I actually found the answer as to why I had all those flowers and no fruit.

I didn’t even bother to look for the answer to that question for years because it all worked out in the end.  It was only after I started learning to save pure seed that I finally learned the truth.  Because, when you want to save pure seed, you must first understand how seeds are produced in the first place. Birds and bees kind of stuff.

So, I learned about how squash reproduce and those lessons not only helped me to become a better seed saver and gardener, but it saved me a whole lot of worry and stress about the health of my plants, too.

Let me start by telling you that you’re squash are just fine.  They’re doing what they need to do to ensure that the plants produce enough fruit (and seed) to propagate themselves.

All cucurbits (that is, plants that belong to the family Cucurbitaceae), including the various species of the Cucurbita genus, such as summer squash, zucchini, winter squash, gourds, pumpkins, cucumbers; and those of the Cucumis genus such as watermelons, muskmelons and cantaloupe.  All of these cucurbit members have separate male and female flowers on the each and every plant.  And if you look, you can see the (very graphic, if I might say) difference between them.

Male Butternut Squash Flower Copyright Jill HendersonFemale butternut squash flowers. Copyright Jill Henderson

As you know, all flowers are made up of several parts, the most noticeable being showy petals and sepals. The shape, color and scent of these flower parts are designed to attract specific pollinators like bees, butterflies and moths.  Some plants, like our cucurbits, produce flowers that are intentionally attractive to pollinators – particularly bumble bees.  Flower petals often act as landing pads to direct pollinators deep into the heart of flowers, where the sexual organs are located.

In plants with separate male and female flowers, each flower plays its role in reproduction.  In a female flower, the pistils are the reproductive organs. Each pistil is made up of a stigma, style and ovary.  The ovary is essentially the womb of the plant, where fertilized ovules grow into seeds.  In the case of vegetable crops, the ovary is the portion of the plant that becomes the fruit or vegetables we eat.  It’s easy to tell a female flower from a  male flower because from the very earliest stages of development, female flowers emerge with a miniature fruit attached to the base of the flower.  In most cucurbits, the stalk by which the flower and ovary are attached to the plant stem is short, to non-existent.

Female Butternut Squash Flower Copyright Jill Henderson

On the other hand, the male sexual reproductive organs are known as stamens, which consist of a thin filament that supports the anther, which in turn produces the pollen that fertilizes the female flowers to produce viable fruit.  In squash, the male flowers are held aloft on long petioles or stems. They are always the first flowers to appear on the plant.  And this they do in profusion long before the female flowers ever open!


The Garden Seed Saving Guide by Jill Henderson   The Garden Seed Saving Guide

Save money, become more self-sufficient and avoid GMO’s by saving seeds!  This excellent resource for beginning and hobby seed savers takes you step-by-step through every aspect of saving your own seed in plain English.   Look inside!


That’s right, the reason you don’t have any fruit for the first two or three weeks of flowering is because the male flowers always come first.  Why?  I have two theories on this:

The first “male flowers first” theory is that the plant needs more males to females for breeding purposes.  When you hand pollinate squash, you want the pollen from three or four male flowers for every female flower you’re pollinating.  That’s insurance for inbreeders like squash – it improves the likelihood of reproductive success and genetic diversity all at the same time.

My second theory (and of course, they could both be right) is that the male flowers show up early to attract a certain amount or kind of pollinator, which the squash need to complete sexual reproduction.  No pollinators, no fruit – at least not for cucurbits.

Male and female flowers and immature fruit on a yellow crookneck summer squash. Copyright Jill Henderson

So there you have it in a squash shell – why your squash don’t have any fruit on them… at least for right now.  But don’t worry, they will and your neighbors will be locking their screen doors to prevent any more zucchini “gifts” left while they were at work.

If you want to learn more about how to save squash seed, check out my article Winter Seed Saving: Pumpkins and Squash.  And let me know how your squash are doing this year!

See you in the garden!

© 2016 Jill Henderson  Feel free to share with a link back to the original article.


The Garden Seed Saving Guide by Jill HendersonThe Garden Seed Saving Guide
Seed Saving for Everyone!

Save money, become more self-sufficient and avoid GMO’s by saving seeds!  This excellent resource for beginning and hobby seed savers takes you step-by-step through every aspect of saving your own seed in plain English.

Available in the Show Me Oz Bookstore
Look inside!


Jill Henderson is an artist, author, and the editor of Show Me Oz . Her books, The Healing Power of Kitchen Herbs, The Garden Seed Saving Guide and A Journey of Seasons can be found in the Show Me Oz Bookstore.  Jill is a contributing author for Acres USA and Llewellyn’s Herbal Almanac and her work has appeared in The Permaculture Activist and The Essential Herbal.


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4 responses to “Squash and Cucumbers: All Flowers and No Fruit?

  1. Any advice for my cukes. Here in Pittsburgh they are growing like crazy with flowers. How much longer will they grow and what about the first frost? any advice? It is September 14, 2-16

    • Hi Kim. Once they flower, cucumber fruits grow very rapidly – sometimes only 1 or 2 days until you get usable size fruits. But they are also warm season vegetables that can’t take a frost, so you will likely lose them around that time. You could try to cover them temporarily (use a bed sheet or remay, never plastic) to protect them from a light frost and possibly prolong the season, but chances are they won’t produce much as days shorten and temperatures fall. Next year, you might try starting them indoors about 2 weeks before the last frost and setting them out as early as possible, which will help a lot in your short growing season in Pittsburgh. 🙂 Let me know how it goes!

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