Butterfly Gardening
by Jane Drake, UC Master Gardener

Tracking the flight of a jewel-colored butterfly softly soaring toward the heavens, can lead us to a new view of the most distant corner in our garden. I enjoy keeping notes of which flowers attract a daily dose of butterflies to my garden. Common butterflies in our area include swallowtails, whites and sulphurs, gossamer-wings, metalmarks, and skippers. Fun facts and general needs of Lepidoptera are easily discovered with a regional field guide (identification book) and a pair of binoculars to see the exquisite detail in butterfly wings.

A combination of annuals, perennials, trees, and woody shrubs provide the proper environment for all stages of the butterfly life cycle. Remember that butterflies metamorphose from eggs to caterpillars, then harden into a chrysalis (cocoon) for the pupal phase, and finally emerge as the iridescent winged adult we admire. Butterflies take flight during the day when their body temperature is at least 86 degrees. They have club-tipped antennae and rest with their wings closed. Moths on the other hand, fly at night, have feathered antennae, and rest with their wings open.

Creating an appealing garden for butterflies requires lots of sunshine, some shelter from the wind (a breeze is like a hurricane to these insects), a reliable year round nectar source, host plants, protection from danger/predators, and a source of water, such as a puddle.

A log pile or butterfly house for protection and a rock or two for basking in sunshine will make your garden a safer haven. Natural predators of larvae and adult butterflies include birds, spiders, wasps, lizards, and rodents. Any insecticide that rids your garden of pests will kill butterflies too. Picking pests off plants, Safer soap, or the use of beneficial insects are useful for pest management.

One secret of a successful butterfly garden is providing a generous supply of host plants for the hatched caterpillars to eat. Females are extremely selective when locating a host plant to lay their eggs on (one egg per leaf). For example, monarch caterpillars feed exclusively on milkweed, whereas painted lady's plants of choice are thistles. Anise swallowtails are satisfied with carrots and herbs such as parsley and fennel.

Common host plants in our vicinity include birch, ash, and willow trees; grasses, red clover, nettles, and other native plants; shrubs including lilac, hibiscus, cassia, rose, and privet; and an assortment of perennials and annuals such as yarrow, hollyhocks, Queen Anne's lace, aster, passionvine, penstemons, foxgloves, cleome, and snapdragons.

Occasionally, butterfly species may be pests to their host plants in the larval stage: cabbage white eats cruciferous crops like cabbage and the common orange sulphurs devour alfalfa crops. The mourning cloak larvae may be a pest to the Chinese elm tree.

Nectar plants provide butterflies food for energy, and if your garden lacks in providing nectar, then your winged visitors will fly elsewhere in search of "greener pastures." Butterflies prefer a secure landing pad on the bloom and easy access to the nectar source so composites, panicles, and umbels are preferred flower shapes.

Waves or patches of bloom of varying heights are much more inviting to butterflies than a single plant. Strong colors entice wandering butterflies, which see in the normal and ultraviolet light wave ranges. Red, orange, yellow, and purple blooms with a touch of pink and blue will create an irresistible scheme.

The length of the butterfly's tongue determines which flower it visits for selective dining. Moths take nectar from long-tubed flowers, needing night blooming varieties such as jasmine, four o'clocks, and nicotania. Fragrance also draws a species of butterfly to the garden and its' feet have taste receptors. A few species rarely visit flowers, preferring sap on trees, fermenting fruit, or bird droppings.

Vivid spring flowers might include Mexican heather, lilac, heliotrope, million bells, ageratum, French and Spanish lavender, erigeron, dahlias, and alyssum. Butterflies love visiting bright coreopsis, zinnias, salvia, lobelia, Dahlberg daisy, scabiosa, impatiens, bee balm, liatris, butterfly bush, red valerian, verbena, cosmos, roses and agapanthus flowering in our midsummer heat. Hardy late bloomers include pentas, rudbeckia, gomphrena, tithonia, lantana, chrysanthemum, and asters.

Making a safe haven for butterflies can be a satisfying and fascinating project. This summer enjoy the amazing flying jewels in your garden.

April 4, 2002