Thursday, June 17, 2010

"Old Reliables": My top ten landscape plants (#10 through 5)

When I first started out in the industry as a bright-eyed college graduate, I thought that I would make every single design to be "that" award-winner. The single, seminal design that would make my career, put my client into throws of existential garden bliss, and get me my own show on HGTV. Uh...right. It made my job extremely difficult; every design required an inordinate amount of research and preparation, and I found myself on the hunt for the exquisite, one-of-a-kind specimen plants. I began to feel a lot like a neurotic house cat who chews off her own tail. This lead me to dread the design process and that next landscape job.

One of my seasoned colleagues told me "build a palette"---select a few plants you like for sun, a few for shade, a few for dry areas, and a few for wet. Work with those for a while and get to know them like the back of your hand. Then maybe you can add a few more to your repertoire. This was the best advice I was ever given.

In Wisconsin, tough is essential. Cold hardiness is key to success. There's nothing more unpleasant to a client than to lose most of her new (and in some cases, pricey) plants over the winter and have to start over the following spring. In my area, soil is heavy clay---great for throwing pottery, but difficult for getting plants to establish healthy roots. And then there's the inevitable summer drought, heat, and humidity. Dead plants have a way of putting people off. And according to the Japanese, they eminate negative energy...

Since we have a short growing season here, it makes sense that one would try to select plants that will give a lot of bang for their buck. I tend to choose cultivars that bloom for unusually long periods, like over the course of several months. This eliminates the need for complex designs and garden clutter. Sure you can stage blooming throughout the season and create layers of plantings. But why not choose plants that will keep going and going, giving of themselves and asking little in return?

My top ten "old reliables" for SE WI:

10) 'Northwind' Switchgrass (Panicum virgatum 'Northwind'):
Great warm season grass that holds its form through fall and winter. Upright, vase-shape with blue-green foliage and delicate late summer seedheads. Butter yellow fall color that resembles a sheaf of wheat. I use this in mixed plantings, at the back of the border. Best when planted in groups of three or more.
Height: 4-5' Spread: 2-3' Light: Full sun Zone: 2
Photo courtesy of Meadowbrook Nursery

9) Reblooming Dwarf Daylilies (Hemerocallis cultivars): Yes, they are somewhat ubiquitous landscape plants. But with good reason---they are some of the hardest working flowering plants in the business. Many types will bloom nonstop from June through October. Dwarf varieties generally vary in height between 12 and 20 inches high; perfect for middle or front of a border. Many cultivars are now available, but I generally stick with bright colors for greatest impact. My favorites: 'Happy Returns', 'Pardon Me', 'Little Business', 'Eeenie Weenie', 'Crimson Pirate', and 'Aztec Gold'.
Height: 12-20" Spread: 16-24" Light: Full sun (for prolific flowering) Zone: 4-5 Photo courtesy of Copper Leaf.

8) Shrub roses (Rosa cultivars): I say 'roses' in a sales consultation, and some clients bristle. Forget your grandma's tea roses---shrub roses are something completely different. My selections require little if any maintenance, bloom like crazy from early summer through fall, and are generally tough as nails. Now that being said---you will probably see some dieback every spring. No problem. The dead parts of the shrubs are usually brittle and black-brown; cut these parts away. When the plant starts actively growing, you can shape it a bit more, trimming back to an outward facing group of five leaflets. Easy peasy! Not all shrub roses are created equal, however. I have had great success with roses in the 'Easy Elegance' series, and some of the Knockout series; Double Knockouts seem a bit more sensitive than their predecessors. It may help to add 3 inches of compost or leaf mulch over the roots in late fall for extra insulation; pull this off in spring.
Height: 2-3' Spread:2-3' Light: Full Sun Zone: 4-5
Photo courtesy of Easy Elegance Roses

7) Willow Bluestar Amsonia (Amsonia tabernaemontana):
A former colleague turned me on to this plant---it made an appearance in almost all of her designs (thanks, Carrie! I get it now.). This is unusual blue perennial blooms in late spring and early summer, and makes a comeback in fall with yellow-orange, fine-textured foliage. I love this at the middle or rear of a border, planted en masse and allowed to spread out. Try Amsonia with a contrasting, large-foliage plant in front of it.
Height: 2-3' Spread: 3' Light: Sun-Part Sun Zone: 3
Photo courtesy of White Flower Farms.

6) Hosta varieties (Hosta cultivars): Use Hosta to brighten shady spots, combine with more delicate perennials for textural contrast, or plant them in pockets and corners of your yard that require little maintenance. I am crazy for Hostas, all varieties, big and little, blue, yellow, variegated, twisted and puckered. Sizes vary wildly---"minis" may reach only 6-8 inches tall, while large varieties can spread to a whopping 3-4 feet high and wide. Hostas are occasionally bothered by slugs; choose thick-leaved, dark blue varieties for improved slug resistance. A good rule of thumb regarding sun tolerance: the lighter the leaf color, the less shade it requires. I wouldn't recommend full sun with any hosta, but you'd be suprised how much sun some of the yellow and lime green varieties will take. A few of the best cultivars: 'Blue Mouse Ears', 'Chartruese Wiggles', 'Blue Angel', 'Stained Glass', 'Paul's Glory', 'Stained Glass', 'Sum and Substance', 'Guacamole', and 'June'.
Height: 6 inches-3 feet Spread: 12 inches-3 feet Light: Part sun-Full shade Zone: 3
Photo courtesy of Song Sparrow Farm and Nursery.

5) Prairie Dropseed (Sporobolus heterolepis): Low-growing, native WI grass with fine textured foliage. Delicate seedheads appear to float atop arching stems in late summer and early fall. I think that if you roll the seeds between your hands, they smell like buttered popcorn! Good drainage is important, as well as full sun for best performance. Fantastic orange/yellow fall color adds to this plant's list of strengths. I've found that Prairie Dropseed can take a few years to really flourish, but once it gets established it goes like crazy. Great edging plant, or at the front of the border in mixed plantings.
Height: 2-3' Spread: 2-3' Light: Full Sun Zone: 3
Photo courtesy of GardenStew.com

Next blog: Top ten landscape plants (#4 to 1)!

Try this plant: Hydrangea 'Invincibelle Spirit'


Yeah, I'm a sucker for a new introduction plant. I'm a chump for something touted as new and improved, with bigger blooms, spot resistant foliage, or stronger stems. I admit, there have been a few disappointments---namely the 'Endless Summer' series hydrangea, Eupatorium 'Chocolate', and any number of tall Phlox. *Sigh.
I am, however, a perpetual optimist. And after cleaning out the small pie-shaped bed behind our new house this spring and placing our Buddha statue at its center, I thought we needed something special. 'Invincibelle Spirit' is a pink mophead, a new introduction 'Annabelle' hydrangea that grows 3-5' high and wide. 'Annabelle' is a reliable workhorse in these parts---tough and cold-tolerant, with huge domed white blooms in mid-summer and an attractive mounded habit. Since so many of my clients are looking for color, I thought this could be a great new addition to my design palette. If it works, that is. What better place to try it than in my own garden.
So far, so good. Of course when first planted, Hydrangeas are water-hogs. This shrub flags like an old queen after one too many cocktails, but a slow deep watering seems to revive it quickly. I'm terribly impressed that mine (roughly 2' high by 2' wide) already has a ton of buds on it. Blooms the first year---I like that in a plant. And if the color is as spectacular as it has been advertised, I will be delighted. The trick will be getting it through the first winter. I think it's in a good spot, a protected corner with 6 good hrs of sun a day. According to Proven Winners, 'Invincibelle Spirit' is hardy to Zone 3, blooms on new growth, and can tolerate partial sun. I will keep you posted, and if it blooms, post photos.(Photo courtesy of Proven Winners)

Try this plant: 'Avant Garde' Clematis


I've been a fan of Clematis for as long as I can remember. My mother has had the same Jackmanii for more than thirty years, and though it's in a shadier spot now than it once was (thanks to the Norway maple) it's still going strong. For vertical interest and high-impact color, you can't beat it.
This year I installed two clematis on the same trellis, in order to have virtually non-stop blooming throughout the summer. 'Avant Garde' has unique, red flowers with showy pink stamens. This is a free-flowering variety that blooms June-September---the perfect companion for my early bloomer, 'Asao'.
I planted it on a south facing wall that is protected on the north and west sides and mulched it to 2" with your basic bagged shredded hardwood. Keeping the roots cool is essential to clematis success. Couldn't be easier for such a hard-working plant. From the window of our sun room, this combo is fantastic!
Hardy to Zone 4. Give it lots of support and it will grow to 10'. Prune back to about a foot in early spring for denser more vigorous growth.
(Photo courtesy of White Flower Farm)