Sunday, 9 September 2012

Saving Vegetable Seeds - Know What You Are Selecting For

Before you think about saving any seeds - perhaps even before you get hold of the seeds you intend to grow out in order to save seeds from them - ask yourself: what is it that I am selecting for? Because I guarantee you, whether you save just a few seeds or every seed your crop produces, you are selecting for something, and that something will affect your garden, and perhaps the gardens of others, for years to come.

You may say you are not selecting for anything, you just want seeds from the vegetables you grew this year, because you liked them and you want to grow them again next year, and save some money in doing so. If you then pick random fruit from your plants and save a bunch of the seeds, and plant the first few that fall from the envelope in the spring, I can tell you are selecting for randomness and mediocrity. Indeed, it is far too easy to select for exactly the qualities that you don't want, by eating your best fruit and saving the least desirable for seed. For early peas, do you joyfully eat the first pods to appear, and leave the last few pods to form to go to seed? You are selecting for lateness in your early peas by doing that. Oops.

At first, this does not seem probable. They are the same seeds from the same plants, after all. The genes should be the same. Why would it matter if you save peas from a pod with three peas, versus a pod with ten? They are all the same pea, and one pea grows a plant. And yet, it does make a difference; a very noticeable difference over time. The process by which this happens is called epigenetics, and it gets ridiculously complicated, especially if you don't have training in the subject. However, once you realize that better plants and better fruits produce better seeds, even if their genetics are essentially identical to the plant or fruit right next to them, it's fairly straightforward to determine what you are looking for in your plants and start selecting for it.

I had some inkling of this, but it was a note from Ken Allan about Spanish Skyscraper peas that really drove this point home for me this summer. He took a mostly forgotten, run-down old variety, and by careful selection of the seeds he saved and planted each year, brought it back to its full potential as a very desirable variety. The seeds I received (not from him) of this variety had been less carefully saved over the years, and do not fully match the quality that he describes. However, I am confident that by repeating his selection process, I can regain that quality.

I am also pretty confident that this process can, and should, be applied to all the varieties of vegetables we grow in our garden. Here's what we need to do - and not do:

1.) If we want to grow 2 of a kind of tomato, for example, we will not shake out 2 seeds to plant from the packet. We will shake out 6, or even 8, and choose the two that come up the most quickly and strongly, and grow the best. The other 4 or 6 will not be nursed along and planted, because, hey! Wasted seed! Oh noes! They will be discarded. We are selecting for vigour, not randomness and mediocrity.

2.) If we want to select for earliness (and in this climate, we generally do) we will be sure to select from the first few high quality fruits to appear on the plant, and not wait until the season is three-quarters over, before we say, "Oh, yeah! Need seed" then pick some of the later forming fruits. On the other hand, there are early seeds that should not be saved: the last lettuce, the last spinach and the last radishes to go to seed are the ones you want for seed. Carrots that flower the first year are good for neither soup nor seed.

3.) We will not save seed from malformed fruit, or fruit which has been damaged by insects or mold, or very small fruits, unless very small fruits are what we want, and generally they aren't. Usually I am looking for the intersection of earliness and reasonable size/volume, and those are the qualities that should determine which seeds are saved.

4.) We will also consider the overall quality of the parent plants. A weedy, struggling plant may produce a fine looking fruit with fine looking seeds. But if a plant of the same variety is producing similar fruits and seeds, but is much more vigorous and healthy, then that's the plant from which you should be saving seed. You may wish to select for more compact plants, but be sure you are not mistaking poor growth for natural compactness. Likewise, if you want plants that produce over a long season, be sure to select seeds from the specimens which produce the longest. If you want plants that produce a lot of fruit, select seeds from plants which are producing a lot of fruit.

5.) The easiest fruits to save seeds from are the fruits that produce the most seeds. In peas and beans, this is almost always desirable, and you should save seeds specifically from those pods that contain the most seeds. In tomatoes it almost certainly isn't - who likes a seedy tomato? Some tomato varieties are naturally more seedy than others, but you should be sure that the tomatoes from which you save seeds are on the low end of average compared to other tomatoes of the same variety when it comes to the quantity of seeds. In cucumbers, melons and squash, the desirability of higher or lower number of seeds may depend on other factors: how are the seeds placed within the fruit, do you eat the seeds, and are they small and tender, or large and tough? All these things must be considered, but often you should be selecting for fewer seeds.

6.) It's actually hard to see all the things we are selecting for. I've seen it pointed out that if you always start your melons, squash, cucumbers etcetera in pots and plant them out, you are selecting for melons, squash and cucumbers which are amenable to starting life in pots. If at some point you decide you want to direct seed these plants, you may find that your saved seed doesn't deal with direct seeding very well. A lot of the seed we buy has been selected for mechanical seed separation and processing... how does that affect the variety? You know it does somehow; not least in that there has been no selection for best quality - it's randomness and mediocrity all the way. Here is where the home gardener has a real advantage. Hand selection of fruits and seeds is slow, but the difference in quality quickly becomes real. Very small seed houses who grow their own seed may be able to replicate this, but they have to know what they are doing and not take shortcuts that save them time and bring in more money. Hmm. Good luck with that. (I do think there are many people out there doing very good work on this front. But still, being small is no guarantee of quality.)

7.) It's not just early bolting that needs to be avoided. How well does the vegetable keep, both holding in the field once ready, and once harvested? How long do you want it to keep? How well can they be transported and displayed, if you need to do those things?

8.) How well do your selected parent plants cope with extreme weather? Hot and dry? Cold and wet? Still and muggy, or howling gales? Late or early frosts? Fungi, blights, and plagues of caterpillars? Sooner or later, you will have them all, and so much more. Watch for these things, watch your plants adapt - or not - and keep selecting.

9.) Well, heck. How did I forget this one until now? It's probably the most important. You want to save seeds from vegetables that taste good. Better than good! Delicious! If it isn't delicious, what's the point? This can be a little harder with some vegetable than with others. I mean, if you've eaten it, how can you save seed from it? For things like tomatoes, melons, etc, not a problem - you eat the fruit then save the seeds. For peas and beans, you will have to assume that all the peas or beans on one plant taste like all the other peas or beans on that plant. You will generally be correct. Lettuce, brassicas an other leafy things are not a problem. For things like carrots, onions and beets, you may need to take a core sample! A healthy plant will survive that. But before or after winter storage, as those three are all biennials? Perhaps that will depend on when you expect to eat them.

10.) This one is actually going to be fairly hard, and we will have to find ways to work around it. But, we will attempt to grow a sufficient number of plants to maintain reasonable cross fertilization and genetic diversity. We will look up the minimum number of plants needed, and actually try to provide that number. That means starting more plants than needed, so as to only be crossing the best - perhaps twice as many as needed. In some varieties, that's a lot of plants. Bringing in new seed by purchasing or trading, and saving seed over multiple years are strategies to help keep that genetic diversity up.

11.) Also difficult, preventing cross pollination from undesirable sources, including weeds and other people's crops. Here you need a working knowledge of how much segregation of plants is necessary to give you a level of seed purity that you are comfortable. So you need to know that, too. You will need to know and implement strategies to keep cross pollination happening where you want it to happen and not happening where you don't want it to happen. These will vary from crop to crop.

12.) The above is all about selection on a micro-level. Keep in mind selection on a macro-level, too. What plants do you want in your garden? Are the plants you are growing now the plants you want to grow in the future? If the climate changes, do you need to change the varieties you grow altogether, or can your current varieties be adapted? Does it, in fact, make sense to plant things that can cope with all extremes of climate, knowing that half of them will struggle because they are not right for whatever season develops? It well might. We are entering a time of flux, when one season is not guaranteed to be very like the same season a year ago, or next year.

13.) ADDED 14/09/12: Forgot this one, but it's important. Many vegetables suffer from Cytoplasmic Male Sterility. It's common in carrots, onions, cucumbers (I think)... and other too, I'm sure. Hybridizers like this quality, but savers of open-pollinated seeds should work to keep it out of their vegetables.While I don't really understand all the ins and outs of this, what it basically means is that you have plants which are not producing pollen (what we consider the equivalent of sperm in people) and either you don't get seed, you get smaller quantities of seed (because there is a little pollen) or if you get seed it's being pollinated by something else... which you may or may not realize. Hybridizers like this because they can sell you seed for vegetables and know that you cannot save seed from them... you have to go back to them and buy their seed every year. For seed savers though, that's exactly not the goal.

14.) Another one I forgot; less cataclysmic than the male sterility problem, but consider how easy your vegetables are to pick. Peas and beans are the ones where this becomes really important. It's frustrating to be out there having to carefully pick each pea or bean with both hands, so that you can detach the pod without tearing up the plant or even yanking it right out of the ground. Basically, the more fruits the plant has, the more important this becomes. It's fine to have to use clippers to remove squash from a bush that only has 3 or 4. Picking hundreds of peas is another story though.


Sometimes you will have only a very few seeds for a variety, and that's all you can get. Plant them, and save every seed they produce. You are selecting for all the genetic diversity you can wring out of this pathetic little gene-puddle. Fair enough. But once you have achieved a certain reasonable number of seeds, all the above begin to apply. In general though, do your best to start off with sufficient good quality seeds from a reliable source. Check also that they in fact match the description of the variety to which they belong. (Not always the case, unfortunately!)

And finally, once you have more good-quality seed for a desirable vegetable than you can use yourself, share that seed far and near. This is not mere generosity, but a form of seed saving in itself. Your flood or fire, tornado or drought will not wipe out all your hard work. Growing food is a commitment to both nature and humanity. Cast your bread upon the waters, and let it return to you in its own time and way.

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