Some seeds need treatments beyond just planting in soil to germinate. Most of these treatments mimic the natural environment and the requirements of each variety of seed.
Seed stratification is a simply process used for extremely hard-shelled seeds. Stratification can occur in several ways and mimics the gnawing nature of animals that may eat these seeds. This includes seeds such as those from dogwoods and gourds.
The importance of seed stratification is that it scratches and/or nicks the seed coat so that water can enter the seed and start the germination process.
To begin the process, simply take coarse sandpaper or a file and sand the entire seed coat. If you have several seeds, just line a can with sandpaper and tumble the seeds in the can. Another approach one can use is to attach sandpaper to two broads. Then, place the seeds between the boards and move the boards back and forth.
For some hard-shelled seeds, this is all that is required but for other seeds the process is a little more involved.
Seeds that have extremely hard seed coats require nicking. This is done by making a notch in the side of the seed that is deep enough so that the white insides show. Once the seeds have been nicked, soak them in water overnight.
For seeds that are very hard but not extremely hard, the process starts with a presoak overnight. The next day simply nick the seed coat.
Repeat the process of nicking and soaking for those seeds that do not swell up.
Cold treatment of seeds mimics the outdoor environment that many seeds planted in the fall and winter need for germination. But this type of treatment goes beyond the dry cold of the refrigerator. Cold treatment includes elements that the refrigerator cannot mimic such as a certain moisture level, air, cold, and time.
To begin the process of cold treatment requires the seeds to be soaked in water until they are swollen. This can take up to four days but nicking can speed up the time.
While the seeds are soaking, prepare the plastic bags for the next step. This requires the gardener to label the bag with the name of the seed.
After the seeds have soaked and swollen, remove them from the water. Place the seeds in a container of damp peat moss or vermiculite and then place the container inside the plastic bag. Mark on the bag the planting date and a projected date. The projected date is when the seeds can be removed. Most seeds will take between four to 12 weeks of cold exposure.
Another approach to use is to sandwich the seeds between damp paper towels or coffee filters. Place the material in a plastic bag as described above.
Place the prepared seeds in a refrigerator that is kept between 34 and 40 degrees F.
After the cold exposure time period has passed, take the seeds out and let them set in an environment that is kept around 50 degrees F for a few days before planting. Direct seeding from the refrigerator is too much stress for the seed and will reduce ones germination rate.
Gibberellic Acid-3 or GA-3
Gibberellic acid-3 is a naturally occurring plant chemical that regulates plant growth. To use this chemical is simple and can be used for seeds that require special treatment such as aging or cold.
To utilize this technique only requires you to presoak the seeds in a Gibberellic acid-3 solution. . This solution can be picked up through seed catalogues and some nurseries. This presoak will cause a rapid germination rate so be prepared.
Smoke treatment of seeds mocks fire-prone areas such as California, South Africa, and the Mediterranean region. This technique requires a unique and unusual tool that can be found in the spice isle. This tool is smoke flavoring or liquid smoke. When picking the liquid smoke make sure that it is organic and only contains water and natural smoke concentrate.
To utilize this technique, simply presoak the seeds overnight in a solution of one part liquid smoke and nine parts water. Another approach is to pour the solution over seeds that have been planted in a flat or container. Only expose the seeds to the liquid smoke and water mixture once.
This treatment begins with placing seeds in a flat or pot. Do not cover the seeds with soil but instead utilize several inches of pine needles or straw. Then, catch the material on fire and allow it to burn until completely gone. Do not remove the ash but instead water in the seeds in the flat or pot as usual.
Adding these unique techniques to ones gardening toolbox will help one become a more successful gardener.