When you were a child, you probably called annuals “flowers.” This designation, albeit unscientific, neatly describes their biological destiny. While permanent plants like shrubs and perennials flower for only a few weeks before their blossoms fade, annuals bloom with lightning speed and can keep going for up to five months. They have to flower at such a frenetic pace because they don’t have much time to reproduce themselves. As their name implies, they complete their entire life cycle in a single year or less: they germinate, bloom in a blaze of glory, set seed, then die at a point when their longer-lived perennial neighbors remain puny and plain. That’s why you’ll plant a new crop of annuals each season – except in cases where they self-sow.
Butterflies are attracted to bright-colored flowers, especially those with reservoirs of nectar and nutritious pollen.
Photo Credit: ©2000 Dolezal Publishing/John M. Rickard
Petunias span the summer season with continuous, prolific bloom production. Because they expend so much energy, be sure to
fertilize them at least monthly as they grow and flower.
Photo Credit: ©2000 Dolezal Publishing/John M. Rickard
There are several types of flowers besides annuals.
Foxglove is an example of a biennial flower. It sprouts and grows foliage in its first year, blooms and sets seed in its second, then dies. Plant biennials as second-year nursery starts if you want their color added to your annual garden
Photo Credit: ©2000 Dolezal Publishing/John M. Rickard
Practically speaking, any plant that you intend to keep in your garden for a year or less is an annual. However, not all the candidates you’ll consider are true annuals that go from tiny sprout to the compost pile in under 12 months. Some are perennials that behave like annuals in many climates. Others are biennials with life cycles of two years, growing foliage in the first season, then blooming and dying in the second. If you want to use biennials as annuals, start them indoors, purchase them as second-season transplants or find quick-blooming cultivars and sow them early. A few perennials mentioned have tuberous roots or rhizomes that die in cold weather. You can replant them each year or dig up their roots and bring them inside for replanting the following season.
Annuals are divided further into three major categories, according to how well they tolerate freezing temperatures: hardy (able to survive repeated hard frosts), half-hardy (able to survive light frost) and tender (killed by frost). Hardy specimens are so frost-tolerant that they can usually be planted in autumn to winter over and provide flowers the following spring.
As you might expect, most warm-season annuals are frost-tender, while most cool-season plants suffer in excessive heat. Warm-season annuals prefer the warm soil and air temperatures that characterize summer in most of North America and Europe. Cool-season annuals, on the other hand, fade and even die in the intense heat of midsummer in many climates and must be planted very early in spring. A few cool-season selections are so fussy that they’re intolerant of both frost and heat – they do well only in areas with a long, mild growing season.
Why is it worthwhile to know such botanical details? Simply, it can prevent you from experiencing the No. 1 cause of annual-garden failure: planting the right annual at the wrong time.
To avoid ending up with annual heartbreak, the first thing you need to ask yourself is: “Where am I?” This is a practical question, not an existential one. If you plan to grow pansies, it makes a difference whether you’re in Portland, ME; Winnipeg, Canada; or Puerto Vallarta, Mexico. The good news is, regardless of where you live, you can grow almost any kind of annual – providing you plan around your growing season and climate.
After you’ve determined the length of the growing season in your area, you’ll need to know something about the prevailing temperatures in your region. Just because Portland, OR, and Charleston, SC, both have long growing seasons, it doesn’t mean both cities have the same annual gardens at the same time. The trick is to match the type of annual you’re planting with the time of year it will thrive in your area. In some cases, growing the annuals you want may require you to start them indoors. You’ll still be able to keep all these annuals on your list – providing you know your climate and are realistic about how much time you have to give them.
