'Navitar' can offer some benefits of native plants, but at what cost?
Q. I have heard the term "nativar" and was wondering if such plants can replace native plants and still be effective as a producer of food for wildlife?
A. A native plant is defined by the USDA as a plant that is a part of the balance of nature that has developed over hundreds or thousands of years in a particular region or ecosystem. Only plants found in this country before European settlement or has arrived by natural means since are considered to be native to the United States.
Native plants are adapted to local climate extremes and often have resistance to regional pest problems. Using native plants in your landscape can reduce the need for water, fertilizer and pesticides. They are vigorous and hardy, so can survive winter cold and summer heat. Most important, native plants provide food and shelter for birds, butterflies and other desirable wildlife.
However, while gardeners are interested in using native plants, many shy away from them because they find such species look "weedy" and not that attractive.
And, so developed the nativar. A nativar is a cultivar and/or hybrid of a native species. A breeder starts with a native plant, and then changes specific cultural qualities to enhance a plant's aesthetics or hardiness. The new versions of natives help to sell the idea of native plants to landscapers and gardeners, who are often looking for a visual pop that native plants don't always deliver. Nativars often display greater flower number and size, more intense flower color.
For example, Echinacea coneflowers continues to command popularity, with new varieties appearing every year Unfortunately, these Echinacea cultivars are sometimes sterile (bad news for goldfinches, who want the seed) and often have a "doubled" flower form (bad news for pollinators, who can't effectively reach the pollen and nectar). Finally, one complaint from gardeners is that they don't always seem to do well in subsequent seasons. To avoid disappointment, it is recommended that these nativar coneflowers be used as annuals or very short-lived perennials.
The question still remains: Can nativars replace natives and still produce a sustainable landscape? The questions that must still be answered are:
• Is it going to change the number of caterpillars (a key protein source for baby birds) that it can sustain?
• Is it going to change leaf chemistry which can end up poisoning caterpillars?
• If color patterns change, will some specialized pollinators not be able to find it.
Each gardener must decide if they will be a "purist," growing only native species, or if they will accept these cultivated varieties.
Q. When it comes to gardening, what is the difference between a frost and a freeze?
A. According to the National Weather Service, frost is when the temperature of the Earth's surface falls below 32 degrees. This forms thin ice crystals that can cover the ground. Since a frost is temporary, you can protect your plants by covering them or bringing them indoors the night the frost is predicted.
On the other hand, a freeze is when the temperature is expected to remain under 32 degrees for an extended period of time A freeze generally spells the end of the growing season for tender plants.
• Provided by Mary Boldan. Master Gardener Answer Desk, Friendship Park Conservatory, Des Plaines, open 9 a.m. to noon on Monday, Wednesday, Friday and Saturday. Call (847) 298-3502 or email Cookcountymg.com@gmail.com.