If you, like me, are planning to save seeds from the garden this year, you might also (like me) be wondering how many plants for each crop it will take, to get good seeds.
I have done some seed-saving before. Most of what I know is from a really great book about seed saving, Seed to Seed, by Suzanne Ashworth, that provides excellent and helpful information. Some of the information it contains, for a wide range of crops, includes
- how long seeds can be stored
- some regional growing information
- how/when to harvest crops for seeds
- pollination details
- how far apart different varieties of one crop should be kept, to keep from “crossing”
The book also includes, for some crops but not all, how many plants should be grown to get good seeds. The difficult part here is the “but not all”.
I have done some checking around, in various sources both online and in libraries, to find solid recommendations for how many plants should be grown for the crops I want to save seeds from.
This is what I found:
Different resources recommend different numbers of plants for seed saving for each crop.
As an example, for okra, I have seen that one (1) is the minimum number of plants to grow for seed saving. Another source suggested that 6 is a minimum number, and still another suggested that 10-20 is the recommended number.
That seems like a pretty big range, and for gardeners working with small spaces, the difference in space taken up by one okra plant versus twenty plants can be critical. Which number is right?
How many plants should I grow for seed saving?
Most sources do not explain exactly how the minimum number is chosen, but I found a source that offers options, and a “why” for each option: the book The Seed Garden: The Art and Practice of Seed Saving, edited by Lee Buttala and Shanyn Siegel.
The book offers three categories for how many plants of each crop to grow for seed-saving. These are the categories:
- Number of plants to grow for viable seeds
- Number of plants to grow for variety maintenance
- Number of plants to grow for genetic preservation
For example, cowpeas (AKA Southern peas, such as black-eyed peas) are primarily self-pollinating; each one flower contains everything it needs to make one pod of peas. The planting suggestions for seed-saving are these:
- For viable seeds: one (1) plant
- To maintain the variety: 10-25 plants
- For genetic preservation: 50 plants
This is where I need to tell you that I have not read the whole book. I found this information in a huge excerpt of the text online. This means that I do not have full explanation of the three categories. However, until the book arrives in my mailbox, I am going to hazard a guess, since they seem pretty self-explanatory.
The lowest number “for viable seeds”, which is just one plant in the case of some self-pollinating plants like cowpeas, may be geared toward seed-savers who are mostly focused on saving money through not buying seeds as often. When seeds are saved from just one plant, the odds of losing useful genetic diversity are higher than if seeds are saved from more plants. Eventually, the crop could lose vigor.
Evidence of this loss, such as in less robust plants or lower productivity or less delicious veggies, could take a few years to be seen, or it could take a lot of years.
Eventually, the seed-saver would need to buy another packet of seeds to start again. In the meantime, however, the gardener has not had to buy seeds for this particular crop.
This strategy has the benefit of saving money, but it also gives the seed-saver more room for other crops in a small garden.
Two gardeners, two strategies: growing okra for seed
The planting recommendations in the book, The Seed Garden: The Art and Practice of Seed Saving, for okra are similar to those for cowpeas. Okra is another crop that is mostly self-pollinating.
My Louisiana sister, two years ago, grew one okra plant in her small garden; she saved seeds from one pod of that plant. There are enough seeds in one okra pod that she doesn’t need to buy seeds, or save seeds from another pod, for a few years. This is garden-economy in action!
My okra goals are different. For starters, my family eats a lot more okra than one plant will provide. Also, I have a variety that I hope to maintain, which means that I need to grow more plants if I am planning to save seeds from the garden.
The larger number of plants would be a problem if they had to be grown every year; they take up so much space! However, okra seeds can stay “good” for 3-4 years, if stored properly. This means that I do not need to grow the larger number of plants (~25) every year.
The long life of okra seeds means that I can skip growing the larger number of okra plants for at least two years, and, in those years, I can use the space to grow and save seeds from other crops.
Also, since I will have saved a LOT of seeds in that one big year, I will have plenty of okra seeds to share with other gardeners.
How many plants to grow for other crops?
I pulled some of the planting recommendations from the book The Seed Garden, to make the table shown below. The table includes the crop name and three planting recommendations, for how many plants to grow, for a short list of common garden crops, for the three different seed-saving goals.
The book includes information for MANY more crops. If a crop you are interested in saving seeds for isn’t in the table above, you may, like me, need to buy a copy of the book.
How much space will this take in my garden?
Our garden crop plants come in a wide range of sizes, and some will make mature seeds faster than others.
You can see that the recommendation for genetic preservation for arugula is 80 or more plants. That sounds pretty daunting, but arugula plants are small.
I can easily grow 80 or more plants in a 3×3 foot block of garden space. Arugula leaves can be harvested through the winter, to add to salads, then the same plants will produce flowers, then seeds, as the weather warms in spring.
For me, arugula is a crop worth saving seeds for, using the recommendation for “genetic preservation”, and there is enough room in my garden to manage it every year.
For most crops, though, I will only be able to manage growing enough plants for the other two categories, variety maintenance and seed viability.
Are you planning to save seeds from the garden this year? Which planting strategy will you use?