By Tim Johnson, Senior director of horticulture at the Chicago Botanic Garden.
Gardening as a hobby has really taken off since last year, and there are many plants to choose from for your garden. I often see new plants installed in home gardens that will not perform at their best or will eventually fade away because of where they are installed.
It is easy to get confused when looking through books, magazines and plant catalogs or browsing at a garden center for plant ideas and purchases. Rest assured that there are many great plants to choose from that will thrive in your garden.
Plants perform better, have fewer pest problems and require less maintenance if you match the plants’ cultural preferences with the conditions in your garden. Focus on choosing the right plant for your particular site instead of a plant’s individual beauty or what you see in flower at the local garden centers. Just because there is a plant for sale at your local store does not necessarily mean it will be a good choice for your garden.
The amount of sun and shade in your garden are a couple of key factors to use to guide your plant choices and a good place to start when evaluating whether or not a plant is good fit for your garden.
Placing sun-loving plants in a shady site usually results in spindly growth and few, if any, flowers. The plants will gradually wither away. Similarly, planting a shade-loving plant in too much sun will cause scorched leaves and plants that fade over time.
Knowing a plant needs a half-day of sun may not always be enough information. Keep in mind that a half-day of morning sun will be much different from a half-day of afternoon sun — a partial shade-loving plant may be OK with full sun in morning and shade in the afternoon, but will burn with full afternoon sun.
The west side of your home will be hotter than the east side. Some hostas perform well on the east side of the house with morning sun, while the hot afternoon sun on the west side would burn the foliage, even though both sites have a half-day of sun. There are many different hosta cultivars to pick from, with some having more sun tolerance.
The amount of shade in your garden is also important — is it a light shade, like under a honey locust tree, or deep shade, like that in a more heavily wooded area? A plant that prefers light shade or a half-day of sun will typically struggle in a full, more deeply shaded site.
The type of soil that is in your garden is another important factor to keep in mind when choosing plants. Parts of Evanston have sandy soils that drain well and dry out quickly, while others have the heavy, clay loam soils more typically found in the Chicago region.
Astilbe is a common garden plant that generally prefers light shade and moist, but well-drained soil. If it is planted in full sun and in soil that is sandy and dry, then it will die out, while catmint (Nepeta), another perennial, will prosper in those conditions.
Many gardens in this area have soils with a high pH, in which more acidic, soil-loving plants such as river birch and rhododendrons perform poorly. In time, a river birch growing in a heavy clay and high pH soil will develop chlorosis (yellowing) in the leaves and perform poorly and eventually die.Read up on the plant’s cultural needs to match it to what it prefers to grow in and skip planting it if its needs cannot be met by your garden’s growing conditions.
Many gardeners like to push plants’ limits in order to grow favorite plants, which results in the plants being installed in conditions that they tolerate versus prefer. Special site preparation and maintenance practices can also allow one to grow the plants that are more demanding or not ideally suited to your site’s conditions, if you are willing to put in some extra effort. It is important to buy plants that are hardy in this area, indicated by having USDA Zone 5 within their hardiness range. Plants only hardy to Zone 6 or higher will likely not survive a typical Chicago winter.
Some things to consider about the individual plants include their size, habit, foliage and seasonal interest, such as flowers and fall color. Evergreens provide good structure for winter. There are plants that are resistant to deer browsing; deer will generally eat yews and arborvitae, but leave boxwood alone.
Look for disease- and pest-resistant plants. Powdery mildew is a common disease on phlox — ‘David’ is a phlox cultivar that is resistant to powdery mildew. Go to the Chicago Botanic Garden’s website, chicagobotanic.org, to access Plant Evaluation Notes, which are reports on the performance of cultivars of various plant genera, such as Phlox, to find the cultivars that grew best at the Garden.
Understanding the growing conditions in your garden is an important first step in making good plant choices. Use this information as you research plant choices, or consult experts for advice. The better information you have about your site, the better advice you will get.
For more plant advice, contact the Plant Information Service at the Chicago Botanic Garden at plantinfo@chicagobotanic.org
This article first appeared in the Chicago Tribune.
