However, some plants cross-pollinate more easily than others. Sometimes I want this, but sometimes I don't. For example, chard, beet, and mangelwurzels can exchange pollen. So when I plan my garden, I need to take this into account - what plants am I saving seeds from and where? What isolation distances do I need?
Isolation distance is a tricky thing. Take a dedicated selfer like peas. They have an official cross-pollination chance of 1% and a recommended isolation distance of 4 feet. This is, however, in an industrial setting with pesticides. An organic farm like ours has lots of bees on the peas. What's more, in some parts of the world, cross-pollination chance is as high as 60% (numbers from Carol Deppe's book How to Breed Your Own Vegetable Varieties: The Gardener's and Farmer's Guide to Plant Breeding and Seed Saving).
Isolation distance isn't just distance in space, it is also distance in time. So if I don't want my chard to cross with my mangelwurzels, then I can save seeds from chard this year and mangels the next. Here are some ideas of how I can manage different seed saving rotations.
|The big tall thing tied up with rope is chard going to seed.|
- kale breeding project
- brussels sprouts
- collard breeding experiment
- komatsuna breeding project
I can't remember where turnips fit in this, and if mustards and kales are going to be a problem if they are in the same garden. This needs more research and will be expanded on as I learn more.