Because perennials generally bloom for only a few weeks at a stretch, foliage is all you have to look at for the rest of the growing season. But, if you remember the 1960’s terrarium craze, you know how pretty a garden composed completely of foliage can be. A garden of flowers and no foliage isn’t a pleasant thought. Imagine a musical score consisting only of the melody. When you add harmony, you get a rich blend of tones. Leaves can be the bass notes, the accents, or the whole supporting orchestra behind the soloist flowers. The perennials in this section give you the best of both worlds — beautiful flowers and better than average foliage.

The Grass Menagerie

Flowers and grass are natural partners, occurring together wherever ample sunlight is available. No other foliage plant surpasses grasses for the texture and beauty they bring to the flower garden. Still, if you’ve ever battled either weedy grasses or lawn grasses (click here for more on lawns) growing where they aren’t wanted, you may question the sanity of intentionally introducing grass into the flower bed.

Granted, a few of the ornamental grasses, such as Ribbon grass, are every bit as tenacious and aggressive as crabgrass or quackgrass. These invasive grasses do have landscape applications for extremely difficult sites, and you can use them as ground covers for interesting alternatives to traditional lawn grasses. But for the flower garden, you want to seek out the better-behaved members of this large and diverse group of plants. Look for clump-forming grass varieties or slow-spreading rhizomatous types (those with creeping roots).

If you want the best of both worlds in your flower bed (the invasive ornamental grasses without the invasions), bury a large pot or a section of sewer pipe and plant the “attractive nuisance” inside the barrier, where you can confine its traveling ways. Vigilance is still prudent — check for escape attempts every so often. Some rhizomes inevitably try to go over the wall. Be sure to pull these run-away grasses out before they attempt to take over your flower bed.

Not all grasses are what most people think of as grass. Reeds, rushes, sedges, cereal grains, and bamboo are all lumped together in the same extended family with ornamental grasses. All grasses do share a few distinguishing physical traits. The most obvious is the foliage — long, narrow blades with parallel veins running the vertical length of each leaf. Their understated blooms aren’t flowers in any traditional sense. Grass flowers are feathery or spiked affairs.

Big And Bold Herbaceous Perennials

When you come across a perennial listed at 10 feet (3 m) tall, you’re looking at the Incredible Hulks of the flower bed — herbaceous perennials who die back to the ground in winter to return each spring and quickly grow to the proportions of a large shrub. These plants can work magic on even the smallest garden. Large perennials are real attention-grabbers.

Many garden designers caution against including really massive perennials in the small garden. They fear that small spaces are too easily overwhelmed and dominated by such an imposing presence. But whether or not you include these big beauties in your little flower bed depends entirely on the look you’re after.  ....read more