LIFESTYLE

To grow delicious cucumbers, learn how they reproduce

Lee Reich
This June 2, 2017 photo shows a cucumber flower growing on a cucumber plant at the organic community garden “Huerto Roma Verde” in Mexico City. Cucumber plants bear separate female and male flowers, but only the female flowers yield cucumber fruits. (AP Photo/Leslie Mazoch)

If you are going to venture at all beyond the ordinary in growing cucumbers – and you must if want to eat the best tasting ones – then you should think about how they reproduce.

Cucumber flowers are either male or female and fruits develop only from female flowers. The male flowers supply pollen, which is carried by bees to the female flowers, whose ovaries, once the flowers are pollinated, swell.

Run-of-the-mill cucumber varieties have separate male and female flowers on the same plant. But each cucumber plant is somewhat flexible about its sexuality, pumping out more female flowers in response to better growing conditions. Fruit and seed production, after all, take a lot of energy.

And then there are cucumbers, called gynoecious types, that have been bred to bear only female flowers. After all, why waste any of a plant’s energy producing male flowers?

Gynoecious cucumber varieties tend to yield more fruits and bear them earlier in the season (which is good), but over a shorter period of time (which can be good or bad, depending on how you use the cucumbers).

“Whoa,” you might say, “no way those female flowers can swell into fruits without male flowers to provide pollen.” Good point. That’s why seed packets for gynoecious cucumbers contain a few seeds of standard cucumbers to provide enough male flowers – it doesn’t take many – to provide pollen for all those female flowers. Those standard cucumber seeds are dyed for identification.

Another way to get pollen to a gynoecious cucumber is to borrow it from your neighbors. No need to walk next door, though: Bees will carry it over from as far as a half-mile or more away.

Lastly, you might get a gynoecious cucumber to bear fruit by growing a variety whose fruits develop without any pollination whatsoever – a parthenocarpic variety, which have no seeds.

Parthenocarpic cucumbers look and taste better when not pollinated. Stray pollen on one of their female flowers causes part of the fruit to swell, as if pregnant. Parthenocarpic varieties are ideal for growing in greenhouses.