Do you know what a “perennial” is? If you do, go to the head of the class – because many people don’t know the answer.

Salvia 'May night'

Bring some color into your garden with Salvia x sylvestris ‘May Night’.

Photo Credit: Stephanie Cohen

Daylilies

Daylilies are one of the easiest perennials to grow.

Photo Credit: Stephanie Cohen

Until now…

A perennial is simply any hardy plant that lives three or more years (if you don’t kill it). The difference between a perennial and an annual is that a perennial sticks around season after season. An annual, on the other hand, flowers, sets seed and dies all within one growing season. Its motto is, “Live Fast, Die Young.” The perennial motto is, “Perennials – Live Long, Remember, 70 is the new 50!”

Many beginner gardeners think their annuals are perennials because the plants appear to come back and reflower the next year. Since we don’t always remember exactly where we’ve planted, sometimes we assume it’s the same plant that comes back. In reality it’s more likely that the annual the season before had dropped some seed, and that’s what bloomed the following year.

When it comes to planting, perennials aren’t vegetables lined up in rows like soldiers. They march to a different drummer and are planted in drifts. A drift is simply all the same plants in a contiguous area. We don’t plant a marigold, then a zinnia and then a salvia. We plant all of the same type of plant together, like three asters. When we design with perennials we should work in odd numbers – 1-3 for large plants, 3-5 for medium-sized plants and 5-7 for small ones. Otherwise, it makes no impact. The “One-of-Eachee” school of design makes for a hodgepodge in a perennial border. It’s not good – and it’s not attractive. Now that you know what a perennial is and how to properly group them, the biggest decision you’ll have to make is where to site your perennial border – sun or shade? This is up to you.

The words “full sun” simply means six hours a day of unimpeded sunlight. However, if you can give your plants four hours of afternoon sun – the hottest part of the day – you can still consider your garden as “full sun.”

If you’re planting under trees, shrubs, roof overhangs, trellises or other garden ornaments you have now become an official shade gardener. And despite what some people may think, that’s not a bad thing – shade is not a constraint when it comes to perennials. It’s just another opportunity to plant hundreds of intriguing and colorful plants that prefer those conditions. (Compare this to annuals, where you might be able – on a good day – to name 10 of them that like shade.)

Perennials play well with all kinds of other plants, too. They can be interspersed among groundcovers, underneath shrubs (rather than lumpy mulch piles), in containers, in mixed borders, in herb gardens, in troughs and rock gardens, as cut flowers and, of course, perennial borders. The opportunities to use them are as diverse as perennials themselves. So have fun with these amazing plants – and happy gardening!