Minutes August 20 — Monarch Butterflies and the Plants That Attract Them

Gardeners Exchange Group Meeting 20 August 2016
Location: Home of Susan Brown
Topic: Monarch Butterflies and the Plants That Attract Them
Submitted by Julie Neely, GEG Secretary

Our meeting was held at the lovely home and grounds of Susan and Jack (Jay) Brown. Susan and her husband purchased their home in Falling Waters two years ago in quite a neglected state and have been steadily working to create a sanctuary for plants, animals, and most of all, butterflies. Susan, an active member of the Monarch Watch, is a wildlife photographer and has published a book on the topic, Close Ups & Close Encounters: A View From Behind The Lens.

Monarch Butterflies

We started the lecture with a few generalities about Lepidoptera, butterflies:

  • A group of butterflies, like a gaggle of geese, is called a “flutter.”
  • Butterflies posess some unique traits; they smell with their antennae and taste with their feet.
  • Butterflies can not fly at temperatures below 55 degrees F; in cooler weather they just “stay put.”
  • Butterflies are found on all continents except Antarctica.
  • Butterflies range in size from 1/2 inch to 12 inches.
  • Butterflies go through four distinct life stages: egg, caterpillar (larva), chrysalis (pupa), and finally adult butterfly.

Monarchs are probably the most well-known and recognized butterfly in the world. Awareness of their amazing annual Fall migration makes this tiny, beautiful insect unforgettable. There are four generations of Monarchs born each year; ultimately it is the fourth generation of Monarchs that migrate to warmer climes in the Fall. The first three generations live about two to six weeks. They sip nectar, flitting from flower to flower, always traveling in a northern direction; they mate, lay eggs, and die. The eggs hatch, repeat the life cycle, and eventually the fourth generation is born. Sue called this the “magic generation.” This is the generation which lives approximately nine months and completes the amazing southern migration each Fall, flying at a rate of 50–100 miles per day. The East Coast fourth generation Monarchs, who have been living east of the Rocky Mountains, fly to Mexico; the Monarchs living west of the Rocky Mountains will fly to southern California. These fourth generation Monarchs live through the winter in the warmer locations, clustering together by the thousands high up in very tall trees.

Creating a Butterfly Garden

Adult Monarch butterflies, like other adult butterflies, feed on a variety of flower nectar including that of snapdragons, black-eyed susans, asters, Shasta daisies, butterfly bushes, and others. See Sue’s list of Butterfly Host Plants. Butterflies prefer flat-topped flowers like daisies or flower clusters like butterfly bush flowers, and flowers in shades of red, yellow, orange, pink, or purple but not really white. Native plants are best for the butterflies and easier for the gardener to maintain.

The unique fact about Monarchs is that they will only lay their eggs on milkweed leaves — specifically the underside of the leaf. If milkweed plants are not present they do not lay eggs. So, milkweed is one of the plants to include in your butterfly garden, both for the flowers and the foliage. The seeds should be planted in late Fall and may take two years to germinate; perennial transplants can take a year to come to full potential. Milkweed is actually toxic to most other insects and animals, but “baby” Monarchs (in the caterpillar stage) eat the leaves and are immune to the poison. It seems that the poison is somewhat protective to the caterpillars as birds are less likely to eat the caterpillars on the milkweed due to the noxious taste acquired from the plant.

Butterflies in the caterpillar stage of their life seem to enjoy devouring most of the plants in your vegetable garden but are especially fond of parsley, fennel, and dill. Many gardeners, including Barbara Damrosch, include these baby food plants in their butterfly gardens. If you want to create a butterfly garden you must be willing to sustain all stages of the insect’s life, so include plants for the caterpillar stage to munch on as well as nectar-bearing flowers for the adult butterflies. Successful butterfly gardens are a natural assembly of plants that the butterflies enjoy feeding on, including perennials and annuals planted in a sunny, sheltered location.

Be sure to include a puddling area of shallow water, dirt, and flat rocks either on the ground or elevated where the butterflies can drink and extract minerals and salts from the mud. Remember not to use any chemical sprays (herbicides, pesticides, fungicides, cleaning agents) in or near the butterfly garden, as even small amounts of chemicals can be toxic to butterflies.

Monarch Watch

Monarch butterflies are decreasing in number worldwide for several reasons. The first is lack of milkweed plants; once located almost everywhere, current farming practices and urbanization have almost removed milkweed from the landscape. The second factor contributing to Monarch decline is changing weather conditions; late frosts in locations where cool weather historically was not a factor can decimate populations of butterflies. Members of Monarch Watch organize every year to tag, count, and track Monarchs as they migrate south in the Fall. The process involves catching the Monarchs with nets and attaching a tiny round tag to a specific portion of the wing. Information on each tagged butterfly is recorded and entered into a central database. Tagged butterflies are counted only once, allowing for more accurate estimates of total butterfly numbers.

You can establish a certified “Monarch weigh station” in your yard by following the guidelines listed on the Monarch Watch website. Among other requirements, the weigh station must include at least ten milkweed plants.