Hydrangea paniculata. Photographs by Dreamtime.
A certain time each year is magical to gardeners — a roughly 12-week period when garden centers earn almost half of their annual revenues. It starts sometime in March and ends sometime in June, peaking in April or May, depending on weather patterns. Many plants are in bloom and, suddenly, plants that are not cold-hardy enough for Memphis winters are brought up from coastal areas or pulled out of climate-controlled greenhouses to brighten local gardens. It is a seductive time for inexperienced and experienced gardeners alike.
It is also when customers tend to make many gardening mistakes, intoxicated by the striking display of color. Generally, locally owned, independent garden centers do a better job of helping consumers spend money wisely than do big-box stores. But even the most experienced staff members at those garden centers can only talk to so many customers per day. Moreover, they cannot answer questions they are not asked.
So, how can you avoid careless and unwise expenditures?
Penstemon.
First, the majority of the investment you make in your yard should be plants that can live year-round in Memphis. The most important guideline in determining where a plant can live is its cold-hardiness zone rating. According to the U.S. Department of Agriculture, Memphis lies in Zone 7b. Any plant with a rating of Zone 8a or higher probably could not survive the coldest winters here. Any plant with a zone rating of 7b or lower probably could survive the coldest winters in this region.
But you should be aware of a few caveats. One of them is that large urban areas like Memphis, with lots of people and pavement, tend to be a little warmer than the rural areas in the same region. Thus, Memphis can be thought of as being in Zone 8a, even though it is technically in Zone 7b. Another is that the rule of thumb, when buying a plant for an outdoor, above-ground container, is to subtract two zones. Accordingly, for containers, look for plants with a Zone 6a rating or lower.
Acer palmatum (Coral Bark Japanese maple)
Finally, a third caveat is that cold-hardiness is not the only factor to consider in determining whether a particular plant is likely to do well in Memphis. One of those is the high humidity of Memphis during the summer, another is the stress of an urban environment, and yet another is the degree to which a plant’s root system is able to handle our heavy rains during certain times of the year, contrasted with drought during other times.
Consider doing an inventory of your existing plants and then figuring out which ones will look the best each month of the year. If you have real show-stoppers during certain times, but nothing that shows out during other months, shop to fill the gaps first. When planning your garden, make sure there is some plant or group of plants that has good color each month on the calendar. By all means, enjoy the color that spring/summer annuals and tropical plants can bring, but don’t spend all of your landscape dollars on them before making sure you have year-round interest in your yard.
You’ll need some Hydrangea paniculata for late summer interest, some Camellia sasanqua for the fall, and maybe an Acer palmatum ‘Sango-kaku’ (Coral Bark Japanese Maple) with its bright red bark glowing in the depths of winter. For late winter into early spring, consider some Camellia japonica or Hamamelis x intermedia (witch hazel), and for those long days of Lent, consider Helleborus orientalis (Lenten Rose).
Camellia sasanqua.
When adding spring and summer color to your Memphis garden, by all means buy some annuals, but consider perennials, too. The seasonal plants, tropicals and annuals, tend to have more color and bloom earlier than the perennials, but they live for only a single season.
In contrast, though the canopies of perennials (the above-ground parts) will die to the ground in the fall or early winter, when they go dormant, they will come back the following year, indefinitely. When choosing perennials, know that they are divided into early-blooming, middle-blooming, and late-blooming plants. Choose some of each. And, to benefit our native animals and insects, make sure that at least half of the perennials you plant are native.
Hamamelis x intermedia
According to Mike Larrivee, an expert on native plants in Memphis and a technical adviser to the Memphis Tree Board, his favorite native blooming perennials are Penstemon “Dark Towers” (beardtongue) for early summer, Asclepias syriaca (Common Milkweed, the host plant for monarch butterflies) for mid-summer, and Solidago sphacelata “Golden Fleece” (goldenrod) for late summer. But there are many to choose from, and a good full-sun perennial bed should include at least three early bloomers, three mid-summer bloomers, and three late-summer bloomers for maximum impact.
As long as you do some research and ask the right questions, it’s easy to bring all the colors of the rainbow to your garden.
Asclepias syriaca (Common Milkweed)
