Category: Seeds

In January I posted an introduction to saving seeds.

In this post I would like to go into a little more detail on saving seeds from biennial plants.

Biennial plants are ones that go to seed during their second growing season, usually in the spring. Many people who save their own seeds don’t save seeds from biennials because they think it’s too much trouble, but this isn’t necessarily so. All plants are a little different, and it’s not possible to say everything about all of them, but here are some general tips. Some example of biennial plants are parsnips, carrots, cole plants (cabbage, brussel sprouts, turnips, kale and so on), celery and celery root (celeriac), parsley, beets and swiss chard.

What many people don’t realize is that by saving your own seeds from biennials and other plants is that the resulting seeds will be more suited to your garden and climate than the original seeds, and will likely improve in both productivity and quality of harvest from one year to the next, especially if good roguing techniques (see below) are used.

If you live in an area with a mild climate, chances are good that all you will have to do is let these plants stay in the garden and harvest the seeds in the spring. In some cases, covering the plants with a layer of straw or other mulch can help them survive through the winter.

If your winter is too harsh for the plants to survive, you may need to dig up the plants and store them in a root cellar through the winter. In a few cases you may need to grow them in a greenhouse or similar structure, possibly with heating. In this later case, it may very well be too much trouble to try to save your own seeds.

If you store the plants in a root cellar, you will need to maintain a steady and low temperature and a moderate to high humidity. It does not necessarily need to be underground, but it does need to be protected from the effects of direct sunlight, so probably will need to be north facing. Depending on the type of plants stored, you may need to protect it from freezing, or otherwise provide some source of heat. Plants are normally dug from the garden and stored in wet sand or sawdust for the winter.

Whatever plants you are saving roguing is critical. All seeds will contain genes and traits that effect their suitability for growing in a particular location, their productivity or their quality in other ways. The goal in saving seeds is to select the best plants and consequently the best genetic traits, for growing in the conditions present in your garden. If you are growing cabbage or brussel sprouts, you want plants whose yield is large, solid and attractive. If you are growing a root crop like beets or parsnips, you want only properly shaped, large and good tasting roots. Of course you can’t taste the plants if you are going to save seeds from them, but only save seeds from plants that you think would be the nicest to eat. If you are saving roots, dig them up and look at them! Replant the ones that look nice. Destroy any plants that do not have desirable qualities.

As a rule, plants normally produce large quantities of seeds. In general, it is not necessary to have a lot of plants to have a good seed harvest. It is however a good idea to save seeds from at least a few different plants, as a way of preserving your gene pool.

Once you have selected the plants you are saving seeds from, go around the garden and identify any possible plants that they may cross-pollinate with and figure out how you are going to isolate them. Destroying genetically compatible plants is the easiest way to prevent cross-pollination, but in some cases this is not possible. Depending on the plant, it may be possible to construct a cage or other covering to prevent insects from cross-pollinated the plants. Providing enough distance between the plants may be all that’s necessary.

If you live in an area with wild Queen Anne’s Lace, you will have a difficult time saving seeds from carrots. Queen Anne’s Lace is really a wild carrot and will easily cross-pollinate with what you grow in your garden. Because the pollen from these plants is very fine, and carried large distances by the wind, it is difficult to isolate them with barriers.

Exactly what plants are genetically compatible is complicated, and frequently the source of disagreement between gardeners. The best thing is to ask around for advice, or research the matter on the Internet.

Recently I became a member of the SSE, and a few days ago I got my first seed ‘yearbook’ from them, and I felt it deserved mention here.

It’s really quite an experience to open this seed listing for the first time. Most of us are probably used to thinking a seed company is large if they offer 1000 different kinds of seeds. This year there are 12,284 unique varieties in the SSE yearbook. Besides having all the usual vegetables, it includes fruit trees, garlic, water chestnuts. It includes virtually every ethnic food you have ever seen.

Many of the listings come with stories about how this particular variety was passed on in a family that came from Europe or discovered growing in the wild somewhere. There are many varieties of plants you will never see in a normal seed catalog or sold by a commercial seed company.

All of the varieties are offered by people (756 of them in 2006), or in a few cases small businesses, that grow the plants themselves and will send you samples of seeds or plant cuttings in the mail.

Okay, so what’s the catch? Can anyone get these plant samples? There is not much of a catch, and mostly these are available to anyone who becomes a member and asks for them.

There are a few caveats however.

Although it is not a requirement, there is the hope, that as well as ask for samples you will also grow some of these plants and reshare them. Some of the samples listed are either in short supply or in danger of being discontinued, and are only being offered to other people sharing samples or to people who offer a firm commitment of growing and sharing the plant. The number of samples restricted in this way is very small.

It is also a reality that most people offering plant samples live in the US or Canada, and people living elsewhere have to pay extra shipping and handling costs and will likely not be able to order live plant material like fruit trees or garlic. People living outside of North America also have to pay considerably more for membership, to cover the extra postage for sending membership material.

Finally, when you order plant material you are not dealing with a company, but with 756 individuals. None of them take credit cards, and if you don’t live in the US or Canada you have to think about how you are going to pay them in their local currency. Most of them take cash, and some might even accept foreign currency, but probably not many. If you order 10 packages of seeds, you will probably have to send 10 separate letters requesting them.

For anyone interested in growing unusual plants, this is very valuable resource. In addition, the overall trend of the number of people supporting the SSE by sharing their seeds is in decline, and more people are needed to support it. I would encourage anyone who thinks they might be interested to become a member.

Tomato seeds are one of the easiest types to save. Tomato plants are mostly inbreeding, meaning it’s unlikely tomato plants will cross pollinate with each other and plants grown from the saved seeds will produce more tomatoes of the same type.

Seeds can only be saved from open pollinated or heirloom types. Seeds saved from hybrid types will likely be genetically unstable and lead to unpredictable results.

Ideally, tomato plants will be grown a half meter apart in rows 1 meter apart. Preferably you will grow about 5 of the same type in a row, and save seeds from the middle 2 or 3 plants. In this way, you will have some genetic diversity by using more than one plant, and you will minimise the already small risk of cross pollination by isolating the varieties from each other with a little space. In doing this, your rate of crossing should be far below 5%. If you can’t do this, or you only have 1 or 2 plants of each variety, don’t worry, you will probably achieve good results no matter what.

There are contradictory reports of wild or currant tomatoes crossing with each other and with other tomatoes. To minimise the risk of crossing, don’t grow these types of tomatoes near any other plants except those of the identical type when saving seeds.

Only save seeds from the most tasty and good looking tomatoes to ensure you do not select any that are genetically predisposed to be of poorer quality. If possible, select seeds from the first few tomatoes that ripen on each plant, as these are likely to have the healthiest seeds.

Okay, on to the seed saving part. Fermenting seeds helps prevent some diseases, and also removes the gelatinous coat on the seeds. If you don’t wish to ferment them, just skip the steps below and spread them out on a coffee filter to dry.

To ferment the seeds, first slice your tomato or tomatoes along their equator, and scoop the seeds into a non metallic fermenting container. If desired, you can add a few tablespoons of water, but it’s not necessary. Cover the container with plastic wrap, and poke a few holes in it. Put in a warm place (about 70F or 22C), protected from direct sunlight, and leave undisturbed for 3-5 days. Fermenting is an anaerobic process, meaning exposure to oxygen will disturb it, so the contents of the container should not be stirred. There will be a layer of slimy mold growing on top and, after fermenting, you should scoop as much of this off as possible.

Now rinse the seeds off by holding the fermenting container under slowly running water. Mostly the seeds will sink to the bottom, and everything else will float. By gently helping the debris over the edge of the container with the running water, you will be left with only seeds. If any seeds do float, they are bad, and you can let them wash away.

Now pour off as much water as possible, and put the seeds on a piece of coffee filter paper to dry. Do not use any other type of paper like a paper towel, or the seeds will stick. At this point you have about a week to completely dry the seeds before they start germinating. Place them in an airy place, protected from direct sunlight.

When they are dry, put the seeds in a paper or plastic envelope and store at a steady temperature in a dry place. Only store them in plastic if they are completely dry.   Some place dark without frequent temperature changes like the back of a closet or cabinet is a good choce of storage location.  Properly stored seeds will last about 10 years.

All vegetable seeds have a limited shelf life. This ranges from one year for plants like parsnips to up to 10 years for plants like tomatoes. Exactly what storage life a particular plant has can be looked up in reference books, or perhaps found on the Internet. Some examples of common plants are peppers (3 years), sweet corn (3 years), other corn (5-10 years), and so on.

Storage times for a particular variety of plant seed are very dependant on good storage practices, and as such few commercial suppliers of seeds will guarantee their products beyond the year in which they were sold to you. Because germination rates for seeds will only decline with their age, most seed companies as a matter of good business practice and with the intention of providing the highest quality product to their customers will only sell seeds from the most recent year’s harvest.

What happens if you try to grow old or improperly stored seeds? The quality of seeds is measured by their germination rate. Older or improperly stored seeds will have a lower rate of germination, or may not germinate at all. If you are unsure about the quality of some seeds, nothing will be lost by just trying to plant them and seeing what happens. If they grow, the plants will likely be just as healthy as plants grown from fresh seed. If you want to test some seed for the ability to germinate, just set them in a few layers of paper towels and keep moist and in a warm place for about a week.

The most important things to keep in mind when storing seeds are to keep them dry, at a steady temperature and out of direct sunlight. Beyond this, a cooler temperature is better than a warmer one.

A good choice of location to store seeds is the refrigerator. You must insure they stay dry, and this can be done by first putting the seeds in a plastic or glass container.

For very long term storage of seeds, one of the best containers is a glass jar with a rubber seal. This is because all plastic containers will leak a little bit over time.

For long term storage of seeds they can be frozen. Before freezing seeds, you must ensure they are dry enough or the water inside of them will expand during freezing and damage the seeds. A rule of thumb is if a seeds breaks when you bend it, it is dry enough, otherwise it is still too moist. Freezing seeds can increase their shelf life up to 10 times what would otherwise be possible, for example tomato seeds can be stored up to 100 years, peppers 30 years, and so on.

One of the most common ways of drying seeds for long term storage is to use silica gel. There is a special type of silica gel with a color indicator, that is very useful to seed savers. The most common type available in the US is blue when dry, and changes to light pink as it absorbs moisture. Because this type of silica gel contains small amounts of cobalt, which is poisonous and a potential environmental contaminate, there are also other types available. In Europe the most common types are orange changing to blue, or orange changing to colorless. Color indicating silica gel can be reused over and over, by drying it out in an oven at about 125C (250F) for several hours until it reverts back to its original color.

To dry seeds with silica gel, place them together with an equal amount by weight of silica gel in a closed container. Let it sit for 7 days. Beans and other legumes should not be over dried or they may be damaged, so you may wish to dry these for only 5 days. If you suspect you have over dried a particular batch of seeds, you may wish to germination test the seeds to make sue they will still grow.

Information published on saving seeds can often be vague and contradictory. Of course all plants can be a little different, and it’s not often practical to discuss each one in detail. A number of books touch on the subject, and Suzanne Ashworth’s Seed to Seed is one of the best. In this article, I am going to try to give a brief introduction to some of the more important issues on the subject.

The home gardener has to take care that different varieties of the same plant don’t cross pollinate with each other. Exactly what will cross can sometimes be difficult to determine. For example, there are 4 different types of squash, none of which are genetically compatible and will not cross with each other. On the other hand, if you have Queen Ann’s Lace growing wild near your garden, it will easily cross pollinate with carrots you try to save seed from, because it is really a wild carrot.

The Latin name of a plant can often give you a clue. Plants with the same Latin name will almost always cross with one another.

Various techniques can be used to prevent plants from cross pollinating, and one of the easiest is to save seeds from an ‘inbreeding’ plant. Inbreeding plants are self pollinating, and generally don’t cross with neighbouring plants unless either special effort is made to force cross pollination or if insects cross pollinate the plants. Seed savers can usually save seeds from these plants without any special care. Examples of inbreeding plants are beans, peas, wheat and most other grains, tomatoes and peppers. These are some of the easiest plants to save seeds from, and in many cases what you harvest for seed is the same as what you harvest to eat.

Another way of preventing cross pollination is to only plant one of a particular type of plant at a time in your garden. It’s actually possible to plant more than one, as long as you insure that only one of them blooms at a time. For example it’s sometimes possible to grow two varieties of corn, one late and one early, and save seeds from both if they bloom at different times. It’s always possible to grow more than one type, and harvest all but one before any of them bloom.

If plants are separated by a sufficient distance, the pollen is unlikely to be able to travel from one plant to another. If you know what the safe isolation distance is for the particular type of plant you are trying to grow, it’s possible to grow more than one type separated by this distance.

Finally, there are a number of techniques to cage or cover plants to prevent pollen from travelling from one plant to the next, but still grow them side by side. I won’t get into this here.

What happens if plants cross pollinate when you try to save seed? It depends on the plant, but often the results are obvious. Since all plants traits are based on pairs of genes, half from each parent, if two very different plants cross pollinate, the results are likely to be very unique. In this case, you can simply discard the unwanted plant. In some cases, slow genetic contamination can occur over time, but this is less common.

Generally as a home gardener, if you use common sense, are as careful as possible, and accept small amounts of crossing as inevitable, you will be fine. Of course commercial seed producers have to be much more careful.

Beyond inbreeding and outbreeding, there is another classification that is important to seed savers: annuals and biennials. Annuals typically grow through the summer, and produce seed in the fall. Biennials require two complete growing seasons before they produce seed. In areas with hard winters, the plants often need to be dug up and brought inside during the winter. Example of biennials are cabbage and related ‘cole’ plants, celery, parsnips and carrots. Most vegetables are annuals.

While it’s not exactly saving seeds, many heirloom gardeners grow plants that reproduce by root division. Example of this are garlic, shallots, multiplier onions, and so on. Since there is no pollination with these plants, it’s not necessary to worry about genetic material spreading between plants. Because there is always the chance of small genetic variations, the process of roguing described below is very important to keep in mind.

Roguing is a very important issue for seed savers. Basically, this means ensuring you are only selecting seeds from the best plants possible. By selecting seeds from the best growing and most productive plants over a few years, you can develop your own seeds best suited to your own local growing environment.

It’s also important to save seeds from at least a few plants, if possible. This is because there are always small genetic differences from one plant to the next, and saving seeds from more than one plant will help preserve these beneficial differences.

As a rule, you should not save seeds from the same plants you eat from, and there are several reasons for this. Many plants will become inedible after going to seed. Often going to seed means the plants life cycle is complete, and it just dies. Otherwise, if you eat some part of the plant before it goes to seed, like the leaves or the first few seeds the plant produces, the plant has to expend energy replacing these, which means less resources will be available for strong and healthy seed production. If you do save seeds from the same plant you harvest for food, you should first save seeds, then harvest for food later.

Beyond keeping all of these things in mind, saving seeds is just as simple as letting plants first bloom, then collecting seeds from the seed pods that develop.

A future post will explain techniques of storing seeds.