Thursday, February 18, 2010

Greenhouse Vegetable Pollination

We just received a question about greenhouse vegetable growing from Shaun via email. Shaun writes:

I have some questions about gardening in greenhouses... how are vegetable plants fertilized inside a greenhouse? Do you allow bees in the greenhouse? I've only done open plot gardening, and I know from my short experience that you have to have bees to fertilize tomato plants and zucchini and all the rest. These are all flowering plants that require insect pollination. I've been thinking about getting a greenhouse for my backyard, but I'm confused about the pollination issue.


Great question! For us, this isn't really an issue because our plants are only started in a greenhouse and then moved outdoors. But here's what you need to know:

Things like tomatoes and peppers are self-pollinating and therefore, only need to be gently shaken regularly to get the pollen moving(immitating the wind for example). Things like lettuce and beans will figure things out on their own without any intervention. Lettuce is just leaves, so unless you are looking to save seeds, just let them be.


Other veggies, however, such as zucchini, squash, cucumbers (which have male and female flowers) need a little bit more attention. One method is "painting" pollen from the male flower onto the female flower (or vice versa). You should note however, that there are some self-pollinating cucumber verieties to be found out there. They are often bred for use specifically in greenhouses. But like you mentioned, it is possible to use insects in your greenhouse by sinply leaving a door open (if you've got a door and a window you might even be able to make a cross-breeze and to get that wind in there). This might, however, have the potential of letting unwanted insects in so be careful!

Happy planting!