from The Essential Herbal, Jan/Feb '10
Starting from Scratch with Seeds
Kathy Musser, Cloverleaf Herb Farm
Even though there are plenty of potted herbs and flowers ready for purchase, starting plants from seed can be both economical and satisfying. The cost of a pack of seeds is generally less than the price of a single potted plant. Seed catalogs provide a huge variety of choices. New cultivars, interesting colors or forms, and hard to find varieties are in abundance in catalogs. If you’re unsure of a plant’s color or form or how it will grow in your garden environment, the economical nature of seeds allows you to try a new plant without a large investment. Lastly, there’s the satisfaction of the process. Seed starting gives a hint of spring to come in dreary months. I love the process of starting seeds, transplanting the seedlings, planting out in the garden and harvesting and using these plants. It completes the cycle and provides satisfaction all along the way.
Materials aren’t expensive and are easily found. In addition to seeds, you’ll need lightweight soil-less mix. Try to get one labeled for seedlings, as it will be lightweight and drain well. Assemble your containers – plastic cell-packs, small pots or egg cartons. Make sure there are drainage holes in the bottom of containers or poke holes to provide drainage. Trays to hold your containers and a plastic covering to hold in humidity are helpful. Plastic dome lids are made to fit right over flats or you can use clear plastic wrap stretched over the containers and attached with masking tape.
Place some mix in a bucket, etc. and apply water. Mix thoroughly so soil-less mix is uniformly moist. Fill your containers. Place seed in containers, press lightly into the mix. Label containers with variety name and date sown, using popsicle sticks or plastic stakes. Cover containers.
There is much helpful information on the back of the seed packet. The pack will tell you how many weeks (often 6-8) before setting out to start your seeds. Count back that number from the last frost date in your zone. For example, here in zone 6, our last frost date is usually mid-May. If the packet lists 6-8 weeks, start your seeds between mid-March and the beginning of April. Annuals (those you plant every year) generally grow easily from seed. Since they only grow one year, they must reproduce easily and fairly quickly. Perennials (which survive multiple seasons) often take longer to germinate and do so more sporadically. You may notice perennials often have a longer lead up time than annual seeds.
Seed packets often indicate a variety of needs, light or dark for germination. Seeds requiring light should be pressed into the soil, but not covered. Those requiring dark should be pressed into the mix and covered with more moistened mix. Larger seeds should be pressed into the mix and covered. If light vs. dark is not indicated, I follow a general rule: do not cover very small seeds and do cover larger ones.
Seeds have an outer coating that must break down before germination can occur. Seeds must be kept moist in order to germinate. For many varieties, bottom heat promotes germination. Heat mats are available from garden catalogs. You can also place seed trays on top of the refrigerator, which will provide sufficient, although not constant, bottom heat.
When seeds have germinated, remove plastic cover or wrap. Now the seedlings need sun for growth. Place seedlings in a sunny spot, preferably south-facing. Heat is not important now. In fact, seedlings grown in the lower range of normal household temperatures tend to be sturdier. If you’re growing a large number of seedlings, it’s worth investing in supplemental lighting. If you can set up a table with over-head fluorescent lighting, you don’t need to worry about finding enough space on sunny windowsills. Regular fluorescent tubes are fine. They should be hung on chains so the lights can be raised as the seedlings grow.
After germinating, seedlings need to be watered when they dry out. Overwatering at this point can lead to damping off, a fungal disease, which attacks at the base of the seedling, turning the stem gray and fuzzy and causing the plant to fall over. It can occur fairly quickly and there’s no reviving the plant once it happens. I find that even as seedlings, it’s better to let them dry out between waterings. This virtually eliminates damping off as a problem. Many sources recommend bottom watering. This is fine to do, but the necessary close monitoring of your seedlings for water is the most important factor. It’s easy to tell when soil-less mix is dry as the color lightens considerably.
Seedlings can be transplanted when they develop a second set of leaves. The first set are the same on almost all plants. The second set are actually the first set of “true leaves” and will vary according to the specific plant. Fill pots or peat pots with soil-less mix. Use a small spoon or seedling lifter (available in garden catalogs) to gently lift seedlings from container. Make a hole in the transplanting soil with your fingers and gently place seedling in soil. Don’t handle the seedlings by the leaves. Handle by the stem or better yet, by the root ball. Firm soil around seedling and water. Put seedlings back in sunny window or under lights. As the seedlings develop, you can begin the hardening off process leading up to planting in the garden or containers. Put potted plants outside in a protected spot, out of direct sun and shielded from wind. Bring them back inside at night. Each day, move them so they are more exposed to the elements. Watch watering carefully, as they will dry out more quickly as they’re exposed to more sun and wind. Follow this procedure for 10-14 days. At the end of this time, they can be transplanted to their final location once the last frost date has passed.
Some seeds require special treatment to help break down the protective coating. Very hard seeds can be soaked in warm water for an hour before planting or nicked with sandpaper or a nail file. Some perennial seeds should be sown, then placed in the refrigerator to simulate a cold dormancy period.
Whether it’s to stretch your plant buying budget, grow the perfect variety, or simply enjoy the process, get a jump start on spring by starting some plants from seed.