When we begin to plan or design a perennial flower garden, there are so many different perennial flowers that our choices seem almost unlimited. We begin by ruling out those that are not winter hardy in our zone, and any that are not suited to our overall growing conditions. Often, then, our final selection is dictated by the space available in our flower garden. Space is important, because perennials live for three years or more and over that time, they grow bigger and better! If you fail to plan ahead, you may find your perennials have outgrown their spaces and are so crowded they fail to thrive or need to be dug and divided too often. With a little thought and planning, and researching your plants, you can design a perennial garden to accommodate those mature plants without crowding.
Each different perennial flower has a typical size range, with the ultimate size depending somewhat on the growing conditions where it is planted and on your climate and weather and the care it receives. (Read this if you're not sure about what's an Annual or Perennial?)
Perennial Plants and Size Variation
Perennials, even among named varieties, tend to be more variable in size than the annuals. So although a named variety of the perennial purple coneflower such as "Magnus" (Echinacea purpurea "Magnus") for instance might be described as growing about three feet tall and about sixteen inches across, your plants might grow six inches bigger or six inches smaller, depending.
And of course, the first year they will be much smaller than they will be by the third year after planting when they have developed into mature plants. At that point, most will be ready for division so that they stay vigorous. So once again there will be a size change. This means perennials grow in four dimensions: height, width, depth, and time. That is part of the challenge - and the fun -- of gardening with perennials.
Slow Growing Perennials: Filling Gaps
With slow growing perennials, you can fill in between with annuals for the first year or so. Just take care that the annuals do not overwhelm the young perennials.
In subsequent years, you can continue to fill in any remaining gaps with annuals, or transplant additional perennials -- if needed -- to complete the planting. Some gardeners maintain a propagation or nursery bed of extra perennials for just this purpose.
Keep Records
In any case, keep a record of which varieties you plant so you can refer to it later. This will help you keep track of which perennials and which specific varieties do best for you, and which do poorly.
Or, if you should ever need a replacement, you will know exactly which cultivar you need and where you purchased the original. For example, look at the lavender hedge in the photo. If one plant dies and causes a gap, the gardener needs to know specifically which variety was used and preferably where it came from to guarantee a perfect match.
Or, if it was a plant given to you by a gardening friend, you might have a record of who gave it to you and could beg for another start of it.
The Garden Journal
Now if this scenario isn't the perfect reason for keeping a careful garden journal, I don't know what is!
Your memory may be perfect, but my memory just isn't good enough to trust with important details - especially when your perennials may live for years and years, and the seasons and plants begin to mingle together in your mind. Make it easy on yourself, write it down!
You might also enjoy More Garden Design Ideas Tips and Inspiration...
All Flower Gardens Articles So Far
Copyright May 2006 Barbara Martin
