Perennials Archives

Gardening Basics: Perennials

WheelbarrowSimply Put: Perennials

In the previous post I talked about annuals. In quick summary: seed, germinate, grow, flower, flower, flower, I am so pretty, flower, flower, oh my biological clock is ticking, make seed, die. Time elapsed, one year or less.

Perennials are plants that grow for more than a year (assuming they live; it’s a life style, not a contract with God). They take their time; frequently they don’t even bloom in the first year of growth after the seed germinates.

When they do get around to blooming, perennials have shorter blooming seasons than annuals, or, if they bloom for several months, usually the first few weeks are intense and the re-bloom is more sporadic, sometimes requiring some encouragement on the part of the gardener. This might be something like shearing a couple of inches off of the top of the plant to remove the old dead flowers

Perennials tend to be either cool weather, late winter/spring bloomers or warm weather summer bloomers (but not both). There are even a few fall bloomers. The summer bloomers tend to have longer blooming periods than the spring bloomers.

We know a few things about garden center shoppers. We know that most of you a) shop in the spring, and b) you tend to buy what is in flower when you shop. Because a lot of the fun of perennial gardening is watching things change from day to day and week to week as plants grow and come into flower, you really should visit the garden center a couple of times in the summer to see what’s currently in bloom. Really. It’s for your own good.

Of perennials, it is said that the first year they sleep, the second year they creep, and the third year they leap. So, during the first year after you plant your perennial, not that much happens. The second year (after the first winter) you have more blooms on larger plants, and the third year, they really hit their stride with much larger plants and heavier bloom. Assuming everything goes right.

Most perennials die completely down to the ground in the winter, overwintering with living bits below ground. Or, they overwinter with small tufts of foliage (leaves) above the soil. Technically, these are “herbaceous perennials.” While we are jargoning, we may as well toss in hardy, which means they tolerate some below freezing temperatures. So what we are talking about are hardy herbaceous perennials: you’ll do fine if you just say “perennials.”

There is another outdoor herbaceous group that falls between the annuals and perennials, the biennials: plants that grow without flowering the first year, flower the second, and then die (so bi-ennial; two years). These include cabbage, parsley, and foxgloves. These are sold with the vegetables, herbs, or perennials, wherever they seem to fit the best. There aren’t that many.

Why use perennials? Most people do it to save the effort of replanting annuals each year. This does save some planting time, but for a perennial garden to look good, it does require some care—cutting back old flowers and so on—so planting perennials doesn’t save much time, it just spreads it out. The real reason to choose perennials is that it allows you, should you be inclined, to “paint” with flowers. Perennials change in many dimensions over the season—height, width, color; texture of foliage (fine or broad leaves); how one color plays off the colors of surrounding plants. So, you really get to play. If you enjoy repainting your walls with new colors, then you will enjoy painting the garden with perennials.

Planting tip: perennials are best planted in groups, three or five plants of a given type. If you have a big enough space, you can repeat the group in several spots to “unite” the garden.

How to Handle your Hosta

Behnkes Banks on ‘Shade Aristocrats’

The large, coarse leaves of most hostas tend to break up the monotony found in many landscape designs.

With various sizes, colors, light requirements, foliage shapes and textures, it is possible to fit an easy-to-grow hosta into almost any landscape situation.

When to Plant
Hostas can be planted in this area from March through November.

Where to Plant
Plant hostas where the proper shade conditions exist. Blues lose their color in sun, so they look their best with at least 50% shade. Golds tolerate sun quite well but should be shaded from the mid-day sun. Most hostas prefer dappled shade throughout the day. The soil should drain well and still be able to retain moisture.

hosta-Sieboldiana-ElegansHow to Plant
Dig bed for hostas 12 to 18 inches deep. Make a soil mixture of one third each existing soil, fine pine bark and organic matter such as peat moss, dehydrated manure or garden compost. Loosen root system using a garden cultivator and set plant in bed so top of root ball is even with or slightly higher than garden soil level. A handful of an organic fertilizer such as Plant-tone may be added to the backfill. Firm the plant in and water slowly and thoroughly until the water puddles around the plant. When water has soaked in , a mulch of shredded hardwood or pine bark 1 to 2 inches deep should be applied.

Long Term Care
Water is the most important requirement for hostas, especially the first year or two after planting. We suggest 3 to 5 gallons per week per plant if there is not sufficient rainfall. After the first 2 years, hostas have developed good root systems, and can withstand considerable drought. Hostas can thrive amazingly well with no further fertilizer, but an occasional side dressing of slow-release organic fertilizer in midsummer proves to be quite rewarding. In autumn, after foliage has died from frosts, the leaves should be trimmed off.

Trouble Shooting
The main problem with hostas is slugs and snails. These pests prefer moist, dark areas, feeding mostly on the soft, new, immature growth. Sanitation and a proper watering program are quite effective in controlling them.

Remove debris that provides hiding places and water only in the morning so plants are dry at sunset. Slug bait is also very effective in providing control. Manufacturers’ instructions and recommendations should always be followed with these products. Many of the new varieties of hostas are being bred for more pest resistance. Also, it’s nice to know that the older a plant gets, the more pest resistant it becomes.

Now that you know how to plant and maintain your hostas, sit back and watch them grow.

Purple Coneflower for Your Summer Garden

Echinacea purpurea 'Magnus'-1Behnke Nurseries’ Perennial Department is featuring two cultivars of one of the best summer blooming perennials, the Purple Coneflower, Echinacea purpurea ‘Magnus’ and Echinacea purpurea ‘Rubinstern’ (often translated as “Ruby Star.”)  Although the common name is purple coneflower, they are really pink. Not my fault.

These are similar seed-grown cultivars (being seed-grown they are somewhat variable in height and bloom color, but in general): Both top out at around 3 feet in height, but ‘Rubinstern’ is on average a bit shorter than ‘Magnus’ and has deeper pink flowers.  They both have petals that are relatively horizontal as they open, like a daisy, rather than droopy like a shuttlecock, as is the case for many of the coneflowers. As the flowers age, they become more reflexed.

Blooming begins about now, with heaviest bloom in June and July, continuing to bloom sporadically into August and even September.  Blooming is heavier and longer with established plants, of course.

Siting is best in full sun, in good garden soil.  Like many perennials, if you feed them regularly and water them frequently, the stems will be weak and the plants may fall over. Tough love and all that, once they are established.

They are native to the Eastern and Central United States, and are terrific in butterfly gardens. They also are a good addition to a hummingbird garden, as they attract small insects that hummers like to grab to supplement their nectar feeding. Seed-eating birds like goldfinches will be attracted to the ripening seed heads.

A summer garden or large container combination I like is planting Echinacea with Perovskia (Russian Sage), which has a blue flower and a similar bloom time.  A silver-foliaged plant like an Artemisia or a Dusty Miller makes a particularly nice addition to the two.

‘Magnus’ and ‘Rubinstern’ are in 1 gallon pots, and are 1/3 off of regular price, from June 25 thru July 1st, 2009.

Echinacea purpurea 'Magnus'-2Echinacea purpurea 'Rubinstern'

Lilies – A Splash of Color For Partial Shade

lilies-2Our perennial department has potted lilies. These are budded and blooming plants, 3 per pot, in 3 gallon pots, so they are quite showy! We suggest you enjoy them in the pot as a deck plant, then, when they are out of bloom, that you plant them out into the garden.

Lilies do best in sun or light shade, with cool soil. This is best achieved by having a ground cover to reflect the heat from the soil. (“Tops in the sun, feet in the shade;” clematis have similar cultural preferences.)

There are a number of different types of lilies, including Asiatic (the easiest to grow), Oriental (considered more tricky, but strongly fragrant), and various hybrids that combine aspects of various types, such as the LA hybrids, which are a cross between Easter Lilies (Lilium longiflorum) and Asiatic Lilies, resulting in easy-to-grow,colorful varieties that carry the fragrance from the Easter Lily parent.

We have a good assortment of lilies for you, in various colors and heights: anywhere from natural dwarves that only get 14 inches tall, to others that can reach 5 feet once established in the garden.

For gardeners who have partial shade, are tired of impatiens, and are looking for a splash of color, try some lilies.

Heuchera – Midnight Rose

img_6527As a silverback in the garden center world, and a frequent traveler, I have seen about a billion perennials and heucheras are among my top favorites. The species are North American natives, with small flowers that range from showy (giving rise to one of the common names of “coral bells”), to not-so-showy, which in horticultural jargon we call “interesting.”

Literally hundreds of hybrids have been introduced over the last 20 years, and at least two good books on heucheras have been written. A good website to visit for information and photos is that of one of the primary heuchera breeders, Terra Nova Nurseries,

Heuchera are pretty much all produced through tissue culture, and many are patented; thus, they tend to be fairly expensive (which is one reason that the sale is so exciting). They also have a reputation for being fussy, which means that proper siting is important.

They do best with morning sun, afternoon shade, and good drainage. They are terrific in raised beds and raised planters. They are superb in mixed containers, generally as the “filler” layer in a “spiller, filler, and thriller” combo.

They are used mainly for the terrific range of foliage colors, from nearly black to purple,  silver, caramel, golden, peach, and so on. Even green!! Frequently the edges are ruffled.  The small flowers may be showy, in red, pink and white, especially when multiple stems are in bloom, giving a very fine textured airy look.

If your idea of gardening is to paint with plants, then heuchera should be a mainstay of your palette. The color combinations, especially in mixed containers, are endless. And if sheltered, they may give you a nice show even in winter.

We are proud to have discovered one of the most popular heucheras here at Behnke Nurseries. Terri Poindexter on our Beltsville garden center staff, noticed an unusual plant in a group of black ‘Obsidian’ heuchera.  The plant had pink splotches, as if it had been flecked with pink paint. We submitted the plant to Terra Nova, which patented it, and released it as ‘Midnight Rose,’ consistently one of their most popular plants.

 Page 9 of 12  « First  ... « 7  8  9  10  11 » ...  Last »