If you long to see the butterflies you chased as a child, consider planting a butterfly garden.
Sometime ago, I acquired a butterfly bush whose deep violet flowers had yet to bloom. The very first day a flower appeared, a black swallowtail butterfly materialized as if by magic. I could not remember the last time I had seen a swallowtail in my neighborhood. I was astonished at how the presence of a single flower could make a seldom encountered lepidopteran feel at home in my back yard.
Everyone should grow a butterfly bush or summer lilac (Buddleia Davidii) at least once. Seeing it in bloom is an unparalleled horticultural experience. Imagine thick inflorescences up to a foot long, each consisting of several hundred tiny trumpet flowers. Put your nose up close and the fragrance is that of lightly scented soap, similar to that found in the flowers of California lilac (Ceanothus), another butterfly-attracting plant that blooms in the spring.
The growth habit of the butterfly bush is as uncanny as its flowers. It can grow more than 10 feet in a single season and should be cut back hard just prior to spring in order to make room for its phenomenal annual growth. Left unpruned, the butterfly bush will soon become top heavy with floppy shoots and few flowers.
One notable quality of butterfly bush is its resilience to cold. Grow it in the Antelope Valley or the Tehachipis. A bonus in cold climates is not having to worry about pruning the butterfly bush since nature will do this job for you. During a cold snap, the butterfly bush will die back nearly to its roots, but regrow with great vigor when spring arrives.
There are dozens of butterfly-attracting plants, including California natives such as mahonia, manzanita, coffeeberry, wild buckwheat, toyon, California fuchsia, penstemon and fuchsia flowering gooseberry. Common ornamentals and bedding plants recommended for a butterfly garden include lantana, hebe, spiraea, gloriosa daisy, coreopsis, cosmos, scabiosa, marigold, delphinium, blanket flower, wallflower, lobelia, sweet alyssum, and the many sages (Salvia species).
Several herb plants attract butterflies, including rosemary, oregano, bee balm (Monarda), and lavender.
All plants mentioned thus far produce flowers rich in nectar, which is the mainstay of the adult butterfly diet. However, in order to make a butterfly garden a year-round affair, you need to bring in plants upon which butterflies are inclined to lay their eggs, plants that serve as a source of food for butterfly larvae (caterpillars). These plants may or may not attract adult butterflies.
If you want black swallowtails to lay eggs in your garden, you will want to plant common fennel (Foeniculum vulgare) in among the taller woody ornamentals. Fennel is a relative of parsley, cilantro, carrot, and dill, with soft and lacy foliage to match. It has a licorice fragrance when crushed and, although it develops as a biennial (blooming, setting seeds and dying in its second year) in the Valley, it self-sows reliably upon its demise. Other ornamentals that provide sustenance for caterpillars include mallow, monkey flower, penstemon, passion vine and sunflower, as well as cherry, plum, birch, oak and willow trees.
It is not enough to provide plants upon which adult butterflies and caterpillars can feed. The garden must be protected from wind in order for butterflies to feel at home. Ideally, tall shrubs or trees would surround a butterfly garden. Equally important, a water feature or at least an open container of water or constant puddle should be kept in the garden for the benefit of adult butterflies.