By FPCG volunteer Rebecca

It only took a couple of weeks for my family to get sick of peas.  The first week, they never made it inside — we picked them, shelled them, and ate them in the garden as fast as they ripened.  The second week, the family noticed I was cooking them in everything.  Then I started getting dirty looks — but the peas kept ripening.

So I quit harvesting them for food.  Now, they’re drying on their vines, and I will save the seeds to plant next year.

I find saving seeds really satisfying, not just because it saves the money I’d spend on new seeds, but because it makes me feel that this year’s garden is supplying us for years to come. However, saving seeds works better for some plants than for others.  For several reasons, it should work for my peas.

Since my peas are an heirloom variety, they haven’t been produced as a hybrid of different strains.  Hybrids often grow into great plants and produce well, but their seeds are likely to have a mix of different traits and not grow into good garden plants. If you want to save seeds, planting heirloom seeds is a good way to start.

Another issue with saving seeds is cross breeding. Some plants can be pollinated by different varieties or related species. The plants and the fruits they produce will be fine, but the seeds within the fruits will be a mixture and grow into something different from the parents. The tricky thing is that you can’t tell from the parent plant you grew, or the fruits it produced, whether the seeds they made are the pure strain you started with or a cross with something else.

Some plants, like corn, are wind pollinated. Wind can carry pollen from different strains over long distances, creating seeds that are a mixture of different strains.  Others plants, like squash, pumpkins, and cucumbers, have both male and female flowers.  Insects carry pollen from male to female flowers. If a bee carries pollen from, say, a pumpkin flower to an acorn squash flower, the seeds the squash produces will be a cross between pumpkin and squash. 

Some plants, like tomatoes, have male and female parts in the same flower and can self-pollinate. However, saving tomato seeds can still be tricky.  First, you have to be sure they’re not a hybrid variety — many of the commonly grown tomatoes are hybrids, but as mentioned heirlooms are not.  Second, just because tomatoes can self-pollinate doesn’t mean they will — pollen can still be brought from other varieties – and crosses between different tomato strains often don’t produce good tomatoes.  (Remember, this is only a problem for the seeds; just because you have a great Brandywine tomato doesn’t mean that the seeds will grow into the same thing.)  There doesn’t seem to be any general agreement on how much cross pollination occurs. If you garden in your yard and only grow one type of tomato plant, it’s probably not an issue. I grow several types of tomatoes in my garden, so cross breeding could be a big issue for me. In the community garden, where different people grow different types and they’re fairly close together, saving seeds could be even more problematic.

If you really want to save tomato seeds but are worried about cross-breeding, one neat trick is to bag flowers to stop insects from getting in, thus foiling cross pollination. Remember, each tomato flower (unlike for squashes) has male and female parts. So each individual flower can self-pollinate and develop into a tomato. I’ve read that you can use lightweight sheer cloth, like nylon stockings, to bag flowering stalks on tomato plants. Jiggling them will help shake the pollen around. Once tomatoes start forming you can take the bag off — just tie a string on the branch so you know which tomato to use for saving seeds.  

I think my peas are safe from cross-pollination because even though peas can cross pollinate, they’re not likely to cross with anything farther away than fifty feet.  I don’t think there are any other peas growing within fifty feet of mine, so my seeds should be fine. 

Other plants need to be separated by more than fifty feet to prevent cross pollination, though. I’ve read that squashes need to be at least a mile from other varieties they cross with to prevent cross pollination. Last year I didn’t save squash seeds. I grew delicata squash and three kinds of pumpkins in my yard, and since some pumpkins and squash cross with each other, I didn’t know what I’d get.  This year, I’m only growing butternut squash in my yard, but I’m sure there are pumpkins and other winter squash growing within a mile, so I could get cross-pollination.

I’m going to save some butternut squash seed this year anyway.  I think there’s a good chance it will be pollinated by the other butternut plants in my yard. And, if they’re not, maybe I’ll get something interesting.  A friend of mine grew a pumpkin plant from a saved seed that turned out to be a cross between a winter squash and a pumpkin. It didn’t look like a regular pumpkin, but it tasted delicious.  While some crosses, like those between sweet corn and popcorn, don’t produce anything you’ll want, others could produce something good — and that can be one more fun thing about saving seeds.