Most homeowners welcome butterflies into their yards and gardens, and may even plant specific flowers to entice these “Bright Wings of Summer” to visit. Meanwhile, we loathe caterpillars that nibble trees and vegetables. We forget that if we want butterflies, we need caterpillars.
Gardeners are faced with the dilemma of either sacrificing some of their plants to the appetites of butterfly larvae, or tolerating “weeds” which caterpillars may prefer to ornamentals. Ideally, gardens should reflect the natural landscape, and be planted with native vegetation adapted to the soils and climate of the area. Choose wisely.
Everyone knows that Monarch butterfly caterpillars eat milkweeds, but how can you provide for other caterpillars? Black Cherry, Pussy Willow, Hackberry, Ceanothus, asters, Blue Violet, buckwheat, and passion vine are among many plants that support butterfly caterpillars in various parts of North America. The plants that you select should be compatible with soil and climate, and must be free of insecticides and other chemicals. Yes, many leafy vegetables are on the menu for certain butterfly caterpillars.
The attributes of an adult butterfly manifest themselves early on inside a caterpillar. Wings, a reproductive system, and other body parts begin as “imaginal discs” within the larva. What a great scientific term! The butterfly is literally “imagined” inside a caterpillar. A butterfly caterpillar molts four or five times after hatching from the egg, shedding its too-tight exoskeleton and growing in the brief interval before the new exoskeleton hardens. Eventually, the caterpillar suspends feeding, and searches for a place to enter the pupa stage. The pupa is called a “chrysalis,” and appears to be an inactive phase. However, inside there is wholesale rearrangement of cells. Some genes are turned off, others are turned on. Many butterflies overwinter in the pupa stage, and emerge as adult insects the following spring or early summer. They mate, then females search for host plants their caterpillars will flourish on. Mother butterfly uses a “scratch and sniff” method to detect a good host plant. She literally scratches a leaf, and if her antennae detect the right odors emitted by the damaged leaf, she lays an egg.
Butterflies and other insects in your yard or garden indicate that you are doing things right: You are a good steward of the piece of Earth that you own. Keep it up!