Dr. Grow: A flower of perennial proportions

One of the most common conversations at garden centers in the spring goes like this.

Customer:"I am tired of planting annuals each year. I go to all the work to plant them, and then they die at the end of the year. Next year I have to do it all over again. I want something that I can plant once, and never have to replant."

Clerk:"You should consider planting perennials. They die down at the end of the season but come back each year from roots."

Customer:"Are they hard to grow? I want something that I don't have to water or fertilize."

Clerk:"You'll have to water them when you plant them. Then if we have a dry summer you'll have to water them every week or so. You should probably fertilize them on a monthly basis during the growing season."

Customer:"Well, that isn't too bad."

Clerk:"Quite often perennials need to be staked, or they become too tall and fall over. The spent blooms should be removed to encourage blooming longer than two to four weeks."

Customer:"You mean perennials don't bloom all summer long. I want flowers that bloom all season long."

Clerk:"Although there are a few perennials, such a moonbeam coreopsis and stella d'oro daylilies, that bloom all summer long, most bloom for just a few weeks."

Customer:"I want something that blooms all summer long."

Clerk:"You can encourage blooming by dividing the plants on an annual or biannual basis. This is usually done during the spring."

Customer:"You mean that sometimes I have to stake perennials, divide them, and dead-head them. Do they bush out so much that I don't have to weed around them?"

Clerk:"Keeping a perennial garden weed free is something that needs to be done on a routine basis. Unfortunately many people can't tell the difference between weeds and perennials. Sometimes when they start wedding, they remove all of the perennials that were planted in the garden and leave the weeds."

Customer:"Maybe you need to show me where the annuals are."

As you can see form the above conversation, many people are unaware of the characteristics of perennials. A lot of TLC goes into the care needed for a beautiful perennial garden.

What are the advantages of growing annual flowers versus perennials? The most obvious advantage is bloom time. Annuals are bred to bloom all during the growing season. Only a few perennials bloom all season long.

Some annuals, such as petunias, need to be dead headed (removing old blooms), to encourage seasonlong blooming and to keep the plant well groomed. On the other hand impatiens, begonias, salvia, and alyssum need no dead heading to encourage blooming.

Although some annuals, such as wave petunias, spread out a lot, they are not invasive. At the end of the season, cold weather kills them. On the other hand, some perennials, such as violets, can take over a garden. Once out of hand, they are hard to control even with the use of herbicides.

Because annuals die at the end of the year, no dividing needs to be done to encourage vigorous growth and blooming. This task needs to be done on a routine basis for most perennials.

Annuals have been bred, hybridized, and tinkered with so much that most come in a wide range of hues, sizes and shapes. Although there is considerable interest in perennials today, plant breeders have not worked with them as much as they have with annuals. The variety of color, size, and texture is not there yet in perennials.

If you like a lot of color in your summer garden, I suggest you continue to use a lot of annuals. If you're convinced you want to grow perennials, then experiment with a few each year to see how they grow, and whether they do well in your yard.