Seed Preparation: Cleaning, Storage and Stratification
One of my first hubs was called Selective Seed Saving: Plant Hybridizing Anyone Can Do. It is one of my special garden topics. Hybridizing is that part of gardening I first fell in love with. I like talking about plant genetics. It is still one of those technical aspects a home hobbyist can embrace and master. There are of course specialized scientists who study internal genetic mysteries. Yet, a common every day gardener can still create extreme beauty and functionality with the smallest of efforts.
I should point out that this article will provide information about more commonly grown plants. I do encourage you to research each and every plant you choose to save seed. You will want to learn about where a plant originated. In other words, try to determine how a plant evolved to a habitat. This will give enormous advice how you should proceed with your seed preservation. For example, one of the plants you may choose to save seed from is a water lily. After reading about how a water lily grows, where it grows, when it grows and other information you will realize that like the crown of the plant itself, the seed of a water lily must not dry out.
Great sources of information are garden clubs. The larger the organization the more likely it is that online seed saving instructions, germination requirements, stratification and other concerns will be listed. Since I grow daffodil, daylily and hosta seeds, I made sure to check out the American Daffodil Society, the American Hemerocallis Society and the American Hosta Society home pages for cultural information. Not all plants have large organizations to support their growing enthusiasm. Still, with the world at your finger tips and 6 billion people living on it, I am pretty sure you will find someone, somewhere who you can contact for advice if needed. Today we will talk about less exotic types of plant seed.
I want to talk about plant seeds that grow in a Midwestern United States environment. All the seed I collected this summer I have been storing in brown paper bags. In some cases the seed is collected in small plastic containers. I have been drying these seed all summer. I am fortunate that my only roommate is Becca, my dog. She is rather on the “big boned” side and does not bother my bags that litter the living room. You will need your own indoor space that you can keep these undisturbed. Air conditioning controls the level of humidity that can influence drying time.
Some seed can be collected and dried right in small containers. Seed from Cleome, Rose Campion and Larkspur come to mind. Most plant seed are not so easily cleaned while being gathered. This seed will require cleaning. I collect most of my seed while still in pods, still attached to the plant and dry them thoroughly in a brown paper bag. Paper helps wick moisture that a plastic bag only intensifies. Since some seed I collect starts in the spring I am usually down to only a path through all my brown grocery bags littering the floor by the time fall comes around.
I begin cleaning my seed in the fall when my outside chores leave me the time to deal with this project. I do continue to collect seed well past frost for some plants. So, I begin cleaning those I know I will not collect anymore. You may be surprised to know that, as I suggested in the seed saving hub, the few radish I chose to produce seed were on the most ideal radishes I had growing this season. Some have been making seed since May and will continue to make seed until it freezes. They have been a matted mound of small white flowers all summer. Not bad for a vegetable!
To clean these saved pods you will need a large bowl. I have an old stainless steel bowl I save for this. I can rub and crack the pods to release my seed. Once all has been cracked open and extracted I can shake the bowl. This causes the seed to collect in the bottom. I can now remove the larger dried parts that are now on top of the seed. Sometimes the seed is smaller than the screen in your food strainer. This greatly facilitates your efforts.
When the initially prepared seed is back in your metal bowl it is time to remove yet more debris. I use a fan that I can manipulate myself. I have tried using a small electric fan. The problem is that an electric fan produces a steady stream of air at a higher intensity. I have found that using a manual hand fan is the best. It lets me control and direct a small blast of wind that will take out the debris but leave the seed. A small puff of your breath works too.
Some seed is a regular pain in my “behind” to clean. Zinnia comes to mind. The seed of zinnia is about the same weight and irregular shape as the debris you will get taking a dried head apart. To save my sanity, I carefully cut off any old dried up petals on the top. I twist the casing that surrounds all the seed. This lets both fertilized and unfertilized seed and shells that acted as the scaffolding to all come out. I simply use this as is. When I plant in the spring I “over plant” the row with all of this saved seed and roughage. Surprisingly seedlings germinate at about the right distance. Sometimes I thin to make spacing be more ideal. You may find that a bit of clutter in your seed is tolerable.
After you have cleaned your seed to the degree you are satisfied with achieving it is time to store them for the winter. I save small disposable plastic containers throughout the year. These are perfect. They have snap on lids. Often I include a small bit of paper towel (TP is even better) underneath of the seed. This acts as wicking. It draws what little bit of moisture that may happen to precipitate. Be sure to include a small bit of paper with the name of the seed and the year. Properly prepared seed will last for a few seasons. I am still using some seed from lettuce that is 3 years old. That was an especially good year for lettuce.
For some reason I have better luck storing seed in small glass or plastic containers. It seems that if I store my cleaned seed in paper envelopes I do not get the longevity or viability. I think this is because I create a small micro habitat that whose humidity is controlled by the seed itself. In a paper envelope, the humidity level can change depending on how much is absorbed or lost by the paper. I think even these small changes may affect the seed. Still, try for yourself. Don’t exclude storing seed in envelopes. You may not have enough room in your home for the small box with your seed containers.
This is a fancy term used to describe the circumstances under which seed will sprout. All seed have unique requirements for sprouting. My favorite example for this is Bird of Paradise. The seed of this are rather large. They are a bit larger than a good size sweet pea. They are shiny black with an orange Mohawk strip of fuzz. In nature the fuzz makes the seed buoyant. In particular it keeps the opposite side always on the bottom. As the seed washes in the water it scrapes a small area of the protective shell. This allows the water to reach the seed germ. The water initiates seed growth. Wa Lah! A seedling germinates. The shiny black shell protects the seed germ until the shell is scraped open. The beautiful orange fuzz makes this happen.
All seed have their own need. The scope of this is too great for any one hub. That is why it really helps to know the native environment of your plant. This lets you know about weather conditions. Asia is the opposite of the US in that Easter Asia experiences more rain in the late summer and fall whereas in the US we get most of our rain in the spring with less in the summer. Everything you can find out about the native environment helps you to understand how to get your seed ready to sprout.
Tomatoes are native to Central America. They were imported to Italy and other Mediterranean areas. Therefore, because those areas never or infrequently freeze I can assume my saved seed just needs to be kept at regular room temperatures until planting. Tomatoes are one of the easiest seed to save for starting.
Daylilies originated in central Asia and other nearby temperate areas. They came from places with winter and freezing temperatures. While many newer cultivars are becoming less cold tolerant, as a general guideline, you should still keep your cleaned daylily seed in the salad crisper of your refrigerator for a good 6 weeks. This fools the seed into thinking it has gone through winter and spring is here. Once the 6 weeks are up, just set up your lights and plant your seed. Starting daylily seed after New Year’s was protection against winter doldrums.
Saving seed is really popular. It is really easy. Monsanto did not produce over 60,000 recognized daylily cultivars. It was home gardeners just like you and me. Those heirloom tomatoes you enjoyed this summer were because families decided to collect and save seed for sometimes a hundred years. We are richer for these selfless efforts. Collecting, cleaning and storing seed will add more dimension to your gardening interest.