Month: January 2009

This post is simply a follow up from the last post.

I think confusion over cross-pollination and inbreeding depression are what lead most people to give up on seed saving, but it’s really not a difficult concept!  It really comes down to what Real Seeds say in their seed saving guide:

Do your plants breed in groups?

If yes, then you need to make sure the group is large enough and distinct groups are isolated from one another (these two concepts always go together).  If no, than you have a lot less to worry about when you save seeds.

If your plants breed in groups, then they are referred to as outbreeding plants.  Somehow the pollen from one plant travels to nearby plants, usually by way of insects or the wind. Plants that breed in groups are genetically predisposed to needing a large gene pool to stay healthy.

If your plants do not breed in groups, they are referred to as inbreeding plants.  Inbreeding plants usually have entirely self-contained flowers with both male and female elements, the pollen doesn’t leave the plant and they pollinate themselves.  These kinds of plants are genetically predisposed to being tolerant of a small gene pool.

The only slightly confusing part of all of this is that nature is not usually so kind as to give us something black and white, and there are lots of in between situations.  Plants are usually referred to as mostly inbreeding or mostly outbreeding.

Inbreeding Depression

If you save seeds from plants that breed in groups, with too small of a group, you will eventually have problems with inbreeding depression.  This can result in plants that are no longer suitable for growing, but it often takes a number of generations for these problems to emerge.

This can be fine if you’re only saving seeds for your self, and only intend to grow them for a couple of generations.  On the other hand, this can be a serious problem if you share the seeds with someone else who is unaware of the problem.

Plants that do not breed in groups do not develop this problem as easily, but it’s always a good idea to save seeds from a couple of plants to help avoid the problem.

Start with inbreeding plants

When you begin seed saving, you should start with plants that are nearly or totally inbreeding and therefore do not need to breed in a group with nearby plants and do not often accidentily cross pollinate with others.

Popular examples of this are tomatoes, beans and peas.

When announcing and starting the seed network, there was one recurring theme in conversations I had with others or in comments left here:

Be sure to tell people how to properly save seeds!

Often the person who said this then went on to tell me where the seed saving guide they personally wrote could be found, and suggested I promote it.

I too have written a number of seed saving posts!  Rather than go through them and link to them all here, I suggest using the search box on the front of this blog to search for seed saving.  Most of the posts I wrote were short and introductory in nature.  For many people my posts may be a good place to start, but you will probably want to read further.  For more detail, I suggest looking elsewhere on the Internet.  A few online guides I’ve come across and can recommend are:

Real Seeds

International Seed Saving Institute

Daughter of the Soil

Seed Ambassadors

For those who want to read about seed saving in rigorous detail, I would suggest Carol Deppe’s Book Breed Your Own Vegetable Varieties.  Another good book is Suzanne Ashworth’s Seed to Seed.

The introduction of the Real Seeds guide really says it all, copied below:

You want healthy seed that is true-to-type and keeps well. You need to ask yourself these questions:

CROSSING

• Will these plants cross with any others?
• Is this a good thing, or a bad thing? (Usually bad)
• How does this happen? (Wind? Insects?)
• What can I do to control this?

POPULATION

• Do I need a minimum number to get healthy seed? (e.g. do they breed as group?)
• Or do the plants live on their own and self-pollinate?
• Have I chosen the best plants for seed?

SEED EXTRACTION AND DRYING

• Do I need to do anything special to the seed ?
• Is my seed well dried and well labeled?

The answers are different for each vegetable. So look in the appropriate section below, and you’ll know what to do. Its all pretty easy but you do need to look it up in each case.

If you know the answers to the questions above, for the particular variety you are saving seeds from, then you know how to save seeds properly.

Finding the answers to these questions usually requires some detective work, and it’s not always just a matter of looking them up.  Seed saving is not always an exact science, and many even very experienced seed savers will disagree over some of these points.  It can also depend on your climate and pollinating insects in your garden, as well as your proximity to other gardens or farms growing the same varieties.

The best thing to do is look up all of these questions in at least a few different sources and, where there are conflicts in the advice they offer, try to research further.  You can ask questions here, on other Internet forums or to other seed saving gardeners you trust.  Otherwise, just experiment.

If you are experimenting or are unsure of the quality of the seeds you save, don’t share them with beginning gardeners or without warning the person receiving them!