If you look closely at the plants that make up the Cucurbit family – melons, squash, pumpkins and cucumbers – you’ll notice that there are usually two kinds of flowers on the plant. One is a male flower that produces pollen and the other is a female flowers which, if you look closely, will have a have a small fruit at the base of it. This family of plants is called monoecious because separate male and female flowers are found on a single plant.
Plant breeders have also developed varieties of these crops that are dioecious – particularly cucumbers. This means that one plant will produce only female flowers (gynoecious) and another plant will produce only male flowers (androecious.)
This might seem far too scientific and unimportant but you’ll run across the words “monoecious” and “gynoecious” in seed catalogues and these terms matter. If you grow a single cucumber plant that’s monoecious, you’ll get a crop of cucumbers because that one plant has both male and female flowers. But if you plant a variety that gynoecious, you can’t grow one plant and expect to harvest cucumbers. Packages of gynoecious cucumbers contain a mixture of seeds; there are usually 90% of the all female gynoecious variety that you want to harvest and 10% of a pollinator, a male androecious variety that will produce pollen. If you grow one plant of this kind of cucumber, you’ll have a 90% chance of having a plant with all female flowers, a 10% chance of growing a plant with all male flowers and 100% certainty of having no cucumbers!
So why grow gynoecious cucumbers? All female blossoms on the plants means that there will be a much larger harvest then you’ll get from a traditional monoecious plant. Even taking into account the 10% male plants, a gynoecious variety produces more cucumbers. That’s why most varieties now grown by farmers are gynoecious and a large number of the cucumbers listed in seed catalogues for home gardeners are gynoecious as well.
This year I purchase a cucumber variety called Patio Pickle from Harris Seeds. This variety has short vines and is said to grow well in pots. When I purchased it, I didn’t look closely at the description but when I read the seed packet, I thought, “Oh oh!” Patio Pickle is gynoecious with 12% of the seeds being male pollinators. If I was growing this variety in the garden, it wouldn’t be a problem because I’d be growing a lot of plants and there’d be sure to be at least one pollinator plant. But in a pot, I usually grow only 4-5 plants and with those small numbers, there’s a chance that all the plants will be female.
I decided to take the risk and I planted the seeds – I’m hoping that at least one of the plants is male! (Unfortunately, you can’t tell male and female plants apart until they start to blossom.) There’s a 50/50 chance that my pot of Patio Pickle will produce cucumbers; if not, it’ll just be a nice green vine.
I’ve learned my lesson. For cucumbers in the garden I’ll look for gynoecious hybrids but for plants that I want to grow in pots, I’ll be sure to read the description more closely. With only a few plants, I want to make sure that each plant has male and female flowers. The harvest might be smaller but at least it’ll be certain!