Day 313: Let's talk about lifestyles, shall we? I'm speaking botanically, of course, and I'm talking about the three strategies represented in vascular plants. If you do any gardening at all, you're familiar with the terms "annual" and "perennial" as they apply to flowers. You may also be familiar with the word "biennial," or perhaps not. Simply put, here are what those terms mean. An annual is a plant which blooms the first year from seed. It dies off at the end of the season and, if fertile, the seeds it has formed are capable of sprouting a new generation. You could also call it a one-season plant. On the other hand, perennials are those things which once planted, come back every year from the root. They may or may not be capable of producing fertile seed, but if so, the plants which sprout from those seeds can be transplanted to permanent locations in your garden where, if their requirements are met, they will return year after year. Biennials are a different story. They do not flower in their first year from seed, producing only foliage. The blooms emerge in the second year, and if the seed from them sprouts, those plants will not flower until their second year. If you plant biennials, it's best to do it two years in a row to ensure that you have flowers every year. Examples of garden-variety annuals would be snapdragons, marigolds, lobelia, etc.; perennials might include such things as rudbeckia, hardy fuchsia, hellebore and so on. A common biennial is the hollyhock, and mine like the hot back wall of my house so much that they behave as if they are perennial, but if their seeds drop and sprout, I have to take care not to recognize the first-year plants so that I don't inadvertently weed them out. Normal lifespan for a biennial is two years: one to grow, one to bloom, and then it's done.
Now you might be asking why plants would have three different lifestyles. There are definite benefits to each and, in fact, some plants which are considered annuals or biennials may behave as perennials under certain conditions. Most of our alpine/sub-alpine wildflowers are perennial or annual. Let's look at the advantages to each strategy.
Annuals tend to put all their energy into reproduction. They produce abundant seed quickly, counting on sheer numbers to ensure survival of their species. Some annuals' seeds may lay dormant for a year or more before sprouting, or until scarified by fire which weakens the outer hull of the seed.
Perennials bloom and form seed year after year. Most of these seeds/seedlings rot or are eaten, but eventually, one will take hold and will mature into another seed-producing plant. Perennials tend to be taller, and often shade out shorter annuals. Their root systems can be quite extensive, allowing them to draw nutrients and moisture from the soil during harsh conditions.
Biennials put their effort into growing a sturdy plant with a healthy root system in the first year, securing food reserves in the roots in order to bloom in their second year.
