Plant Sex 101

Plant Sex 101

Part of Ep. 902 Sex and Roses

Join Patti Nagai, the horticulture educator for Racine County Extension, as she reveals the basics of plant sex. Patti explains the difference between male and female flowers on cucurbits such as cucumbers, melons, pumpkins and squash.

Premiere date: Jul 25, 2001

TRANSCRIPT+
Wisc Gardener Transcript: 

Shelley:
You know, most of the time, gardeners don't need to worry about how their plants are reproducing out in the backyard. But sometimes having a little sex education about your plants can be all the difference between a bountiful crop or none at all. We're with Patti Nagai, and Patti's the horticulture educator for Racine County Extension. Patti, when I think about plants and producing, I'm always most concerned about my tomatoes and my peppers.

Patti Nagai:
Great crops to have in your garden, but you don't have to worry about them.

Shelley:
Good!

Patti:
Because tomatoes and peppers have perfect flowers.

Shelley:
What does that mean?

Patti:
That means they are perfectly capable of reproducing themselves without any additional help. They have male and female parts all in the same flower, very close together. This is a hibiscus, which is also a perfect flower. You can see the male parts below that produce the pollen, and then we have the female part above, which will receive the pollen, and then you have successful pollination and you get fruit development. And with tomatoes and peppers, they're all there, you just need a little bit of wind, a little vibration, and you'll get successful pollination and fruit production.

Shelley:
Great, then I don't have to worry about it.

Patti:
Not at all. There's another large group of plants, though, that we commonly have in our vegetable gardens that are a little bit more challenging, and that's the cucurbits. And the cucurbits consist of our cucumbers, melons, pumpkins, and all of our squash, both winter and summer, all are cucurbits. And the reason they're challenging, is that they have imperfect flowers.

Shelley:
And that means what?

Patti:
That means they have male flowers and they have female flowers that are separate from the male flowers.

Shelley:
Okay, well, but I would assume, looking at this, for instance these look a lot like the ones in my garden, we have lots of flowers. So I'm assuming I'm going to get fruit very soon.

Patti:
Not soon. Eventually you will, but all of the flowers on these plants that we have here today are all male flowers.

Shelley:
Oh, that would make it a little difficult.

Patti:
A little difficult. To get successful pollination and fruit development, you must have both male and female flowers open at the same time.

Shelley:
Now how can you tell the difference, how do you know these are male?

Patti:
These are all male because if you look underneath the flower, you'll see nothing, except the stem. If this were a female, you would see a small swollen structure that looks much like the adult fruit that you're expecting. So if it's a zucchini...

Shelley:
A teenie, tiny, little baby zucchini will be there.

Patti:
It'll look like a little tiny zucchini. If this is a pumpkin, you'll see a swollen structure that looks like a little round, green pumpkin. And then you know you have a female flower.

Shelley:
So when in doubt, we need to run out there and look under the petals of our plant.

Patti:
Exactly. So I get a lot of calls about this, it's a very common mistake or problem in the garden when they have a lot of flower production and they're not getting any fruit and they're afraid that there's something wrong with their plant. And this is not just home growers, even commercial growers sometimes have questions about whether or not they're going to get more fruit production, because they have all these flowers, and they're not getting fruit.

Shelley:
So it's normal then, it sounds like, to have a lot of males before you get the females.

Patti:
The male flowers will always come first, and eventually you will get female flowers, but during times of stress or other disorder, you might get an imbalance of male to female flowers.

Shelley:
But as long as you've got both open. What's the pollinator then?

Patti:
The pollinator is the bee. So, as long as you have bees in your garden, and both open flowers, you will get fruit production.

Shelley:
Okay, now that explains why I've had some problems in the past. I've put floating row covers over my pumpkins to keep out the squash vine boars. They have to come off for the bees to get in, don't they?

Patti:
Exactly. And a floating row cover is a great thing to do because it keeps those bad bugs out, but as soon as your flowers start coming on, you need to take that off to give the bees a chance to get in there and do their job.

Shelley:
To do their job. Hey, with this information, I think I can have a great crop.

Patti:
I'm sure you will Shelley.

Shelley:
Thanks Patti. And we're going to recommend two books that will help with this enormous topic.

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