What’s the difference between an annual and a perennial?

Plants fall into two main categories: annuals and perennials. Annuals need to be replanted every year because they won’t survive through the winter. Perennials will come back every year after dying back to the ground in the winter.

So why would anyone plant annuals?

In short, annuals provide a continual display of flowers. Annuals will have blooms throughout the entire season. Perennials, on the other hand, have a flower cycle and will bloom for 2-4 weeks. (The duration of blooms depends on the plant, pruning, and weather.)

How do I know if it’s an annual or perennial?

It depends on what zone you live in. Plant hardiness zones were introduced by the USDA in the 1960’s and groups geographical locations based on their winter temperatures. The map has been updated several times to incorporate additional years of weather information. Not surprisingly, zones are moving with climate change.  The Kansas city area fell into zone 5 (Winter lows reaching -20 to -10)  back in the 1960’s but recent updates now place us in zone 6 (Winter lows reaching -10 to 0 degrees.).  Check what “zone” the flower is considered hardy to, and if it’s in zone 6 or less, it’ll survive the winter if planted in the ground. To learn more about hardiness zones, check out [THIS ARTICLE] from the K-State extension office.

Some gardeners prefer to be conservative in their plant selection and continue to look for options hardy through zone 5

Can a plant be both an annual and a perennial?

Sort of.  There are many species of plants within each genus, and some are hardier than others. That means one salvia plant could be an annual while another species of salvia could be a perennial. Both are Salvias, but they have different characteristics.

Plants are considered annuals or perennials relative to the zone they’re being planted in. That means a flower planted in Kansas City (Zone 6) may be an annual but the same plant may be a perennial when planted in Tampa, Florida (Zone 10).

What are bi-annuals?

A few flowers have a life cycle that lasts 2 years. Hollyhocks are a great example of this. They spend their first year growing leaves and developing roots. They won’t produce flowers until their second year, but the third year, don’t expect them to come back.