Growing from seed

Feb 11, 2015

by Helen Halpenny, Lanark County Master Gardeners

It’s never too early to make plans for your 2015 garden. Already the seed companies have sent catalogues with beautiful pictures and glowing reviews to entice you to buy their regular and newly introduced varieties. Before you order new seeds, get out your left over packets and see what can be reused this year. Many packets of seeds are stamped with the year when they were packaged and the rate of germination you can expect; e.g. “packed for 2015, sell by 12/15 - 86%”. That is like a ‘best before date’ and does not mean they become throwaways after that date. It simply means that the rate of germination will likely decrease the next and in subsequent years. Perhaps only 70 percent of the seeds will grow the next year. Parsnip seed, and probably others, only grow when fresh.

Many seeds are viable for several years when stored in a cool dry environment. To test old seed for viability, pour it into a glass of water. Seeds that fall to the bottom have a good chance of growing. Discard those that float to the top. Another test you can do is to place 20 or so seeds left over from last year’s packet between two moist paper towels for a few days. Remoisten the towels often and lift a corner to check for germination. Use the percentage of germinated seed as a guide for how many to sow. The top of the refrigerator is a good place to do this experiment as most seeds like warmth to initiate germination.

Some seeds have hard coatings that must be penetrated before germination can take place. This treatment, called scarification, can be done in two ways, by nicking the seed coat with a knife or file, or by soaking the seed overnight in a warm water bath. Peas, beans , sweet peas, morning glory and lupins are some examples.

Some seeds need a cold treatment to induce germination. Your seed packet will give you instructions if this process is necessary. To stratify, soak the seeds for a day and combine them with a mix of moist peat and sand. Place the mixture in a plastic bag, and refrigerate for 4-12 weeks. Peony, columbine, gas plant and bells of Ireland are some examples that will respond to this treatment.

If your new seed packets contain more seeds than you can use in one season, store for the following year by folding over the tops of packets and place in a plastic or wooden file box. Keep seeds dry by mixing them with a desiccant such as silica gel, as it absorbs moisture. Good containers for saving seeds are old film canisters, baby food jars, and sealed paper envelopes. Store in a cool location.

Visit our website at www.lanarkmg.blogspot.com or follow us on Facebook or Twitter @lanarkmg.