Mid-February, time for a gardening post. It’s kind of like when you start following your favorite sports team before the season starts, and you are excited because anything is still possible. I am especially excited though because I have a new house, it has a garden, and it is really the first time I have ever had a garden. I’m going to grow some annuals, mostly in pots, but what I really want to focus on is perennials. I’m picking mostly perennials, mostly natives, and mostly plants that are edible in a pinch, although garden for food is not my top objective (my top objective is butterflies and other pollinators, followed by interesting appearance including flowers, followed by food potential). Which brings me to cold stratification. I have started a bunch of seeds in the basement under lights over the last two weeks, but so far nothing has happened. These perennial seeds seem to be tougher than the annuals I have been used to in the past. One reason is some of them apparently need cold stratification.

Where I live the snow is rapidly melting, leaving behind a landscape that seems almost barren and asleep. However, for many native plants and quite a few garden perennials, it is this act of freezing and thawing that awakens them and actually increases their ability to survive and reproduce. Cold stratification is the term used to describe this very basic need; the need for winter.  Winter has the ability to soften the outer seed coat of some of nature’s toughest seeds through the action of freezing and thawing in a moist environment. For many plants that require stratification, this process can take up to 2 months and typically occurs between 34 and 41 degrees Fahrenheit. During that time, the seed coat softens and embryonic growth is stimulated. Eventually, the embryo bursts through the softened coat and begins the process of germination.

For those of us who enjoy starting our own flowers, there are some classic perennials that require a period of cold stratification to increase germination. One example is Echinacea, a personal favorite of mine. Echinacea is a plant gifted with many benefits. Most home herbalists are aware of its medicinal properties and gardeners love it for its beauty, low maintenance requirements and as a mid to late season nectar source for beneficial insects. For these reasons, Echinacea has a place in nearly every garden and farm.  But purchasing mature Echinacea plants from a nursery can be expensive and often some of the most interesting varieties (Rare or endangered native prairie Echinacea varieties have only been available in seed form recently.) are not available commercially. For these reasons, I started growing my own Echinacea from seed a number of years ago. In the beginning, I had mixed success. Without a period of cold stratification, the germination rate for this garden beauty can plummet to less than 30 percent. However, with stratification, it is possible to germinate nearly 100 percent of all Echinacea seeds that are started.

So I’m going to try throwing some seeds in pots in the backyard, even though it is freezing. But 30% doesn’t sound that bad to me. With a packet of 100+ seeds costing $2-4, I can afford to plant 3 seeds for every one that comes up. Still, I’m waiting a bit nervously for that first one…