The glory days for many gardens come in late spring and early summer, when such favored perennials as peonies, irises, foxglove and lupine are at their peak. Then come the long hot days of July and August, when beds and borders grow dull in the summer haze.
It doesn’t have to be that way. A visit to Hillside Gardens in Norfolk, Conn., proves it. There the display beds are bursting with color from mid-June to mid-September, with a peak in late July. Mary Ann McGourty, who owns Hillside with her husband, Frederick, uses their demonstration gardens to show that forethought can ensure any perennial enthusiast a garden that will bloom throughout the growing season.
“You don’t want to have a beautiful show for three weeks and then have it all die back,” says Mary Ann McGourty, who writes, lectures, and teaches about perennials. Many gardeners, she says, especially beginners and professionals strapped for time, do their plant shopping in the spring. At nurseries, they are drawn to whatever is in flower. The result? A garden heavy on early bloomers.
Time of bloom is important, but it is just one of the considerations McGourty says are key to planning gardens that are varied yet harmonious. Color and shape also factor into the equation.
Using these principles, the McGourtys have created an outdoor mosaic that is visually pleasing on many levels. But their basic garden formula is simple: Select the right combination of plants. “How plants work together is the key to a successful perennial garden,” she says.
To figure out what goes with what, “Just start with a plant you like and then find it a partner,” says McGourty. Zero in on the characteristic that drew you to the plant and go from there. For example, you might be attracted to a balloon flower (Platycodon) because of its lovely blue blossoms. Good companions will complement that color.
“Pastels combine with other pastels,” says McGourty, “hot colors with other hot colors. Some colors - white and blue, pale yellow or cream - go with everything.” Reds fall into two categories: blue reds, which go with pastel colors, and orange reds, which go with hot, or bold, colors.
Once the palette is decided, consider the shape of the plants. “A garden with all the same shapes is boring,” says McGourty. Many beginning gardeners plant things like delphiniums, daisies, and poppies because they are familiar plants, but they all have round flowers and the result is monotonous. McGourty suggests mixing in spiky forms such as astilbe, veronica, and liatris with these old favorites.
Then mix in what McGourty calls “filler.” “That’s anything that doesn’t fit the other characteristics,” she says. Examples are baby’s breath and columbine. Voila, you have a garden that will give you pleasure for years to come.
Some examples of good partners for a sunny garden are golden yarrow with blue salvia. They both bloom in early summer, have flowers that are complementary in color and have different shapes. “All that makes them happy partners,” say McGourty.
For midsummer bloom in a sunny garden, you might mix black-eyed susans (Rudbeckia “Goldstrum”) and Russian sage (Perovskia) for a pleasant match.
In the fall, Sedum “Autumn Joy” and late monkshood (Aconitum) will give the garden life and color despite the waning warmth and sunshine.
“All of these plants also have good foliage,” which McGourty explains takes the garden “one step further.”
“It is the foliage that is with you all during the growing season.”
Yarrow and salvia foliage, for example, make an interesting combination because they create a visual contrast: The yarrow has finely cut silvery leaves, while the salvia has broad, dark green leaves.
Astilbe and hosta are classic combinations for the shade garden. “They like the same growing conditions,” says McGourty, “and hosta doesn’t depend on flowers to look good. Ferns are also classic companions for hostas. In the shade garden, things are much more subtle. If you want bright and flashy, you’ll be disappointed.”
Lack of color, especially in late summer and early fall, makes astilbe all the more valuable. “And the deer won’t eat them,” says McGourty, noting that hosta is a favorite deer snack. She suggests substituting Brunnera or Lady’s mantle if deer are likely to roam into your flower beds.
When McGourty designs gardens, she usually uses plants that are equal parts early bloomers, midseason bloomers, and late bloomers. The easiest way to familiarize yourself with the sequence of blooms is to visit your nursery throughout the gardening season instead of just in the spring.
“Going to get your plants in May and planting in spring is a leftover from the days of annual gardens,” says McGourty. Perennials are potted and well cared for at the nursery, and, except during a drought, can be planted through the summer. Just be sure to keep them well watered.
“The two major mistakes beginning gardeners make are not matching the plant to the site and not doing adequate soil preparation,” says McGorty. “If you prepare the soil well, your plants will get a good start and require less maintenance. They will be less likely to have insect and disease problems.”
Once you’ve decided which species to plant, determine how many it will take to make a successful showing.
“The farther away from your viewing point,” says McGourty, “the larger the grouping needs to be. People frequently buy one of this and one of that, which leads to a hodgepodge. You want enough planted together to have a visual impact.”
One or two Shasta daisies right outside your door are fine, but across the lawn you might need eight or 10 for the right effect.
But McGourty’s best tip is probably the simplest and most sensible: “Put the earliest and the latest blooming plants close to your house,” she says. At the beginning and end of the season you are less likely to be out roaming your garden, and having these plants right outside your window or by your back steps can extend the season’s joys.
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