BASICS OF BUTTERFLY GARDENING
by Ann B. Swengel, 1995
Among the most delightful residents already living in your yard are butterflies. These colorful insects are found throughout North America. Some butterflies are quite adaptable to garden settings and readily respond to horticultural efforts to please them. The goal of butterfly gardening is to improve your yard so that more butterflies will live there.
Sunshine. Cold-blooded creatures, butterflies usually begin the day by sunbathing to warm their bodies so that they can become active. Although they often bask on vegetation, butterflies also favor exposed dirt paths, gravelly areas, and pavement because they heat up quickly in sunshine.
Moisture. Many butterflies feed not only on nectar but also on moisture such as dew and tree sap. Puddle edges and moist dirt are especially popular, probably because nutritious minerals leached from the soil are dissolved in the water. Avoid grading out depressions that collect runoff but instead protect them, especially if they catch sunlight after the clouds clear. Such wet spots are especially valuable in arid climates, where butterflies may concentrate around streamsides and other damp areas.
Flowers. The most delightful part of the butterfly garden is the flowery area where adult butterflies seek nectar. Because butterflies are sunlovers, a flower garden designed for them should be in a bright spot (generally a minimum of half sun daily). Some exotic (alien or non-native) garden flowers attract hungry butterflies (see table) but the best way to cater to native butterflies is with native plants. A number of the best native nectar sources occur widely throughout the country and are suitable for horticulture (see table). Sometimes the gardener needs to re-evaluate the worth and beauty of a plant from the butterflies' point of view. The flowers of milkweeds are actually quite lovely as well as attractive to many butterflies. Remember to watch the plants for Monarch caterpillars. Thistles are the rose of the butterfly world - attractive nectar flowers on a prickly plant (that is serves as caterpillar food). The butterflies favor them but your neighbors and community weed ordinances may not. Check local laws before you permit "weeds" in your yard. Some butterfly favorites may never be particularly appropriate for a garden, but they can be tolerated in a back corner of the yard. Some plants to avoid weeding include clovers (especially red), alfalfa, dandelions, dogbanes, heal-all and other mints, pussy toes, various mustards and cresses, and wild strawberry. Please be sure you are not violating any law or neighborly sensibilities before you tolerate these species in your yard. Beware, also, that without careful control, weeds may spread aggressively and smother out other desirable plants.
Selecting plants. Evaluate the plants in the table by consulting reference books on gardening. Research the care requirements, appearance, and flowering seasons of these plants so that you can plant kinds suitable for your taste, site, and climate that will provide flowers throughout the growing season. Since some perennials, shrubs, and trees may require several years or more to establish, you might interplant these areas with annuals for several years to fill in the bare spots and provide more nectar. To discover the best flowers for your butterflies, note which kinds butterflies in your area prefer to feed on when you visit parks and refuges in your region. You may discover that some kinds recommended here are not popular with your area's butterflies, but that some plants not mentioned here are local butterfly favorites.
Caterpillar food plants. Particularly effective butterfly gardens combine a supply of nectar flowers for adults with food plants (hosts) for caterpillars. Include parsley, dill, fennel, and/or carrots in your garden and you may feed the caterpillars of Anise or Black Swallowtails. The brightly striped caterpillars rarely eat more than their share. Some plants serve as food both for caterpillars and adults, including asters, clovers, sunflowers, vetches, wild buckwheat, wild cherries, and wild mustards. The best way to accommodate the eating preferences of caterpillars is to leave some of the vegetation native to your area intact in your yard. Ashes, hackberries, oaks, poplars, violets, and willows all serve as food plants for many kinds of caterpillars. Nettles are also an important larval food plant. If you're lucky enough to have a patch in an unobtrusive location, leave it alone and be grateful! Other lowly but important larval food plants are probably lurking there, too.
Cover. Besides providing native larval and nectar plants, an unmanicured back corner of the yard also provides locations for butterflies to spend the night and the winter in suitable cover, such as tree bark, bushes, grass clumps, and leaf litter. Gardeners in temperate areas should consider letting some of the leaves that fall in autumn work for them as fertile winter protection for their gardens and shrubs. These leaves will also provide safe cover for hibernating butterflies. For arid regions where fire is a hazard, be sure to follow ordinances and recommendations for controlling fuel accumulation (dry plant matter), for the safety of you, your neighbors, and your butterflies.
Pest control. Butterfly caterpillars usually do not overeat their welcome, but other insects can wreak havoc in the garden. Unfortunately, the quickest way to control them (insecticides) is poisonous to your butterfly friends. The butterfly gardener should avoid these chemicals. At most, use them very sparingly and restrict treatment directly to the infestation according to label directions. For other pest control techniques, consult your local agricultural extension office for information on "integrated pest management." This includes growing sturdy, resistant plants well adapted to your area and growing a mix of them, each in small scattered clumps. This discourages any particular insect from overpopulating the garden. Encourage songbirds to raise their broods in your yard, since their hungry nestlings devour vast volumes of worms and caterpillars. Most important, cultivate a sense of indulgent tolerance. After all, the plants and animals are the ones that have to accommodate human tampering with our yards' original habitats. Besides, some of those seeming pests may actually be immature life stages of creatures you like, such as butterflies! Others may be on the plant but not actually causing much damage. And some insects - such as ladybugs and ambush bugs - as well as spiders are actually your comrades, cooperating with you in pest control.
Butterfly watching. Once you've begun to notice and encourage your butterflies, you'll want to approach them closely to enjoy their beauty and observe their activities. You will be most successful if you remember these simple rules: Go slow, go low, approach from behind, and don't cross the butterfly with your shadow. Impatience is the worst temptation when approaching a butterfly, but sudden movement can rapidly flush your quarry. Also avoid being silhouetted against the sky in the butterfly's line of sight. By keeping low against a background of trees or shrubs, you will be less obvious to the insect. If you walk straight toward a butterfly's face, it will easily see you, but if you approach from its behind, it will be less likely to notice you. Don't jinx your approach by letting your shadow cross over the butterfly - this sudden change in lighting may frighten it. When approaching and observing your butterflies, you may work up a sweat. Don't be surprised if a butterfly lands on you to sip your salty perspiration! For a good view from a bit further away, try looking at the butterfly through binoculars. A pair that focuses close (to within 5-10 feet) is most useful for butterfly watching.
What to expect. A little effort to please butterflies is bound to be rewarding no matter where you garden. Even in town with little natural habitat in the vicinity, your sunny flower garden can be an excellent place to watch butterflies, since they will commute in to this source of food. Do not expect hordes of butterflies, however, since complete, intact habitat is necessary to support substantial populations of butterflies. Those gardeners blessed with larger and more natural yards may be amazed at the remarkable variety and beauty of the butterflies living there. Again, do not expect to be overrun with butterflies. Their numbers are in balance with the amount of habitat available for them to use and with the other creatures that also make their home there. Remember, though, that you won't find any butterflies unless you take advantage of warm, sunny days to spend some time looking for them!
Caution. Watch out, though - butterfly gardening can change your life. You will discover your yard is a home not just for people, but for plants and animals, including butterflies, that are having ever greater difficulty finding a place to live elsewhere. An orderly yard with a perfectly kept garden of exotic flowers requires great skill, but a more natural and native look yields not just flowers and vegetables but also birds and butterflies. As novel and alluring as alien plant varieties may be, a native species can be just as lovely and would likely do just as well - or even better. A butterfly gardener easily, imperceptibly graduates from planting some nectar flowers in the border to jealously protecting wild corners of butterfly habitat in the yard - and the world.