Annual versus Perennial Flowers
The very first thing we need to do is understand the terminology. Below we have the terms and the definitions of those terms. This way no one is confused by the terms and we can move forward with the same understanding.
What is an Annual Flower:
An annual grows from seed and blooms and sets seed and then dies in just one growing season. Petunia and marigold are examples of flowers widely grown as annuals. Annuals need to be replanted each spring. Most annuals bloom continuously from spring through fall.
What is a Perennial Flower:
A perennial flower lives for three or more seasons. It may or may not be mature enough to bloom the first year from seed. (Hint: P is for Permanent and for Perennial). Perennials will need periodic rejuvenation and/or replacement, typically every three to five years. Most perennials bloom for only a short period — a week or two or three — once a year.
What is a Biennial Flower:
A biennial grows vegetatively its first year, lives over the winter, then finally blooms in the second season. Once it has bloomed and set seed, it dies. Foxgloves and hollyhocks are usually biennial.
Gardening is never simple. There are always exceptions. Wrap your mind around these:
Half Hardy Annual:
This is an interesting term and
varies in usage depending on your climate. It describes plants that are
perennial in warmer climates but can be grown as annuals in colder climates.
These plants can be categorized with annuals because they will bloom the first
year from seed. They are termed half hardy because although they can handle
frost, they can’t survive extremely cold winter weather. If you live in a cold
winter climate, you would not realistically expect these to come back the next
year. But if you live in an area with mild winters, they may be perennial for
you. Osteospermum is an example of a half hardy annual, as is snapdragon
(Antirrhinum). And in a mid-way location, you may find they survive and
overwinter successfully for you during especially mild years — but not all
Frost Tender Annual or Tender Perennial:
You may see this term used to indicate a perennial plant grown as an annual because it is killed by frost. If you live in a frost free climate, this plant would be perennial for you. If you live where it gets cold enough to frost, you will lose it!
Comparing annual and perennial flowers is a little like comparing apples and oranges. Each type of flower has its own characteristics and advantages.
Annual flowers are those that complete their lifecycle in just one growing season. In other words, you plant a seed (or a seedling plant), it grows foliage, then flowers, seeds and then the plant dies, all in the same year. Annual flowers tend to bloom from spring until autumn frost. Although they must be replanted each year, annuals are hard to beat in terms of showy, season- long color.
Popular annual flowers include petunias, marigolds, zinnias and impatiens. If you’re looking for something a little more exotic than these traditional bedding plants, try spider flower (Cleome), gazania, vinca (Catharanthus) and lisianthus (Eustoma). Some annuals are grown for their attractive foliage rather than flowers, including coleus, Joseph’s coat and snow-on-the-mountain. You can add some edible interest with ornamental peppers, flowering cabbage and okra.
Annuals – Pros
- Annuals are available in a wide variety of sizes and colors and only last a year, so each year you can pick new and different plants; annuals are also great fill-in plants while you wait for perennials to multiply.
Annuals – Cons
- You must purchase and plant a new crop of annuals each year.
Perennial flowers are those that grow for three or more years. Although most perennials tend to have a relatively short season of bloom, combining several species in your planting can yield season-long color.
There is no end to the colors, textures and sizes available in perennial plants. Some of the most popular perennials include daylilies, hosta, peonies and garden mums. For a spikey show of blue, try blazing star (Liatris). Or for a delicate bouquet of yellow, try coreopsis ‘Moonbeam.’ For dramatic late-season color, try black-eyed Susan (Rudbeckia) and purple coneflower (Echinacea).
Perennials – Pros
- Perennials require little maintenance and will reward you with blooms year after year; they also multiply, providing you with additional plants over the years for free. Purchase a perennial this year and you will not need to buy new plants.
Perennials – Cons
- Since perennials multiply, they will require periodic thinning. If you do not think the plants, overcrowding will occur and flower production will decrease. Thinning requires digging up some of the plants, pulling or cutting them apart and replanting; this process must be repeated about once every three years.
Benefits of Using Both Perennials and Annuals
- Most gardeners prefer a mix; perennials provide constant beauty, while the annuals give the gardener the opportunity to change things up a bit.
Can’t decide whether to plant annuals or perennials? No need to pick one or the other. Annuals and perennials can be combined in your planting design to reap the best of both!