Tips on creating a butterfly-friendly garden space.
A butterfly is one of the few insects welcome in the garden. It doesn’t bite, sting or crawl over your food. Although nature makes it appear effortless, creating butterfly habitats can be challenging.
There are almost 300 species of butterflies in Canada but less than 100 visit Atlantic Canada and less than 50 are common. An unpaved country road next to a wildflower meadow on a warm, calm day in July is a great time to search for butterflies. And if it is shortly after a rain and there are puddles along the roadside, it’s even better.
Can you recreate this habitat on a smaller scale in your own yard? “Absolutely,” says Carol Goodwin, associate professor in the environmental horticulture department of the Nova Scotia Agricultural College in Truro.
Gardening for butterflies requires a two-step method. First, you need to add plants to feed the caterpillars that are going to become your butterflies. And yes, they will chew up and strip those plants of their leaves. But if you plant the right ones in the right places—a sunny, warm, windless corner—you won’t really care.
Known as host plants, these usually include native plants such as lupins, clover, vetch, violets and plants from the parsley family. Trees include alder, birch, cherry, lilac, serviceberry and willow. Plant them at the back of your yard or behind your regular flowers; the caterpillars will much prefer the host plants and generally leave your display plants alone.
Female butterflies will recognize the host plants and will lay their eggs on the surface or underside of the leaves. These eggs, though camouflaged, are susceptible to many fatal threats from predators and weather. If lucky, after three to 10 days a tiny caterpillar will eat his way out of the egg and keep eating until it gains over 3,000 times its initial body weight (note: include plenty of host plants when building the garden). Then it will find a quiet, protected spot to form the chrysalis where the transformation from caterpillar to butterfly takes place.
Step two is more colourful. Include nectar rich flowers and shrubs in your garden, such as lilacs, lavender, honeysuckle. Butterfly favourites include aster, purple coneflowers (Echinacea purpurea), phlox, Joe-pye weed (Eupatorium purpureum), scabiosa and yarrow (Achillea). Butterfly bush (Buddleja davidii) is another favourite but it’s only winter hardy in zone five or higher.
Butterflies see ultraviolet colours and markings that are invisible to the human eye. The most attractive colours are bold yellows and reds, planted in large swaths of blossoms. One or two plants aren’t enough—five or seven are better. One type of flower, even in a large group, is not as good as several species in generous clumps.
Butterflies are light and fragile and do not want to be buffeted by wind, though they will take advantage of a light breeze to explore farther afield. Therefore, choose a sheltered, sunny spot for your garden. Because they are cold blooded, butterflies need heat and sun.
Include some large flat rocks in your butterfly garden. Place them where they will be warmed by morning sun.
They find it easiest to fly when the temperature is between 24 to 32°C. If it’s cooler, they must rest and soak up sun to warm themselves. This is why you might see one perched on a stone, basking in the sun. It’s also why you should include some large flat rocks in your butterfly garden. Place them where they will be warmed by morning sun.
Water is necessary for all life but butterflies like theirs with lots of minerals. This is what draws them to shallow mud puddles after a rain. To replicate this in your garden, line a wide, shallow hole with plastic, fill with sand or garden soil and add water every few days to keep it moist. Often several butterflies will gather to drink; this is called “puddling” in the butterfly world. But don’t be surprised to see them drinking from a shallow bird bath.
Finally, do not use pesticides in your garden. They kill the good insects as well as the bad. In a healthy, balanced habitat natural predators will generally take care of things. With urban bans on pesticides on the rise throughout Atlantic Canada, Carol Goodwin hopes to see more butterflies in towns and cities. “No garden is in isolation,” she says. What your neighbours spray in their yards affects your yard as well, so talk to them about butterfly friendly gardens.
The life span of most adult butterflies is about two weeks but they are a significant contributor to the natural world. Second only to bees when it comes to pollination, they are an important part of the food chain and a good indicator of environmental health. When you are gardening this summer and come across an ugly caterpillar, remember he may be on his way to becoming your favourite butterfly and treat him gently.
Common butterflies in Atlantic Canada
Canadian tiger swallowtail (Papilio canadensis)
A yellow butterfly with black lines and blue spots on the hind wing close to the body. Females lay eggs on birch, aspen and black cherry trees only once during late spring or early summer. The tiny eggs are green to blend with the leaves, and the resulting caterpillar is a spiky black/brown with a whitish band around the middle.
Red admiral (Vanessa atalanta)
A larger butterfly with a wingspan of up to eight centimetres with a dark brown, red/orange and black wing pattern with white splotches on its forewings. The butterfly has two broods from March through October. Its favourite host plants are of the nettle family (Urticaceae), and the butterflies prefer sap from trees and rotten fruit to flowers.
Great spangled fritillary (Speyeria cybele)
This butterfly has orange wings marked with black above and brown, yellow and white below. The caterpillar hatches in fall but overwinters, awakening in March to eat wild violet leaves. It changes colour from brown to black and produces prickly, black spines. The butterfly emerges to mate once in June or July and feed on a wide variety of flowers.
Painted lady (Vanessa cardui)
Features deep-orange, black-spotted wings, with black and white blotches on the tips. It lays eggs up to three times from May to October. Adult butterflies prefer feeding on tall flowers like thistles, cosmos, and Joe-pye weed. One of the most widely distributed butterflies in the world.
Viceroy (Limenitis archippus)
Resembles the monarch but is smaller, with a similar orange and black wing pattern. The emerging hump-backed larva is olive green with a pinkish-white band around the middle and feeds mainly on willow and poplar trees. The adult prefers asters, goldenrod, Joe-pye weed and Canada thistle.