Photo by Bob Allen, SE Pinal County Master Gardener
Presented by Southeast Pinal County Master Gardeners
By Bob Allen, Master Gardener
Butterflies need our help! And how to help them was what over 100 interested gardeners learned on Sept. 11 at a seminar hosted by the Southeast Pinal County Master Gardeners at the Sol Ballroom at Saddlebrooke Ranch.
Katie Rogerson, Director of Education and Public Engagement at Tucson Botanical Garden, taught this fascinating lecture.
Most of the plants supporting butterflies are shrubs, trees, vines, grasses and ground covers. Most are native to the Sonoran Desert or are non-invasive exotics from arid regions that are no threat to native plant communities. The presentation included 29 species of butterflies most seen in Southwestern Gardens…information about what plants attract them, butterfly life cycles, and what we can do to encourage them.
Let’s start with a butterfly garden. You’ll want to create a stepped effect with tall plants in the back and low growers in the front. Or if your garden is circular, tall plants in the center tapering down in plant size to the lowest growing plants in the perimeter. You’ll need to keep low-water plants together, if possible, and limit the use of plants that require more water.
Locate the garden in a sunny area easily accessible so you can observe butterflies. And provide some shade if none exists.
An effective butterfly garden will include both butterfly nectar flowers and larval foodplants. Nectar should be available most of the year. Try observing butterflies at one or more local nurseries…or ideally at Tucson Botanical Gardens. You’ll want to gather ideas for your butterfly garden.
Avoid using pesticides and other chemicals because these will kill caterpillars and adults. Adult butterflies are most active from Spring to Fall on warm, sunny days when temperatures range between 65 and 95 degrees Fahrenheit. Climate, predation, parasitism and other factors affect butterfly populations. Therefore, expect daily and seasonal fluctuations in the numbers of butterflies visiting your garden or container garden. Pots work very well if you don’t have a yard!
Butterflies are easily the most noticed, well-liked, colorful, and benign insects. Nearly 400 species occur in the Southwest, more than half of the total number in all North America!
Did you know that Arizona has a state butterfly? It is the Two-Tailed Swallowtail. They are the largest species of butterflies in the United States, featuring a wingspan of 3 ½ to 5 ½ inches! The swallowtails’ habitat includes canyonlands, foothills, valleys and woodlands.
Crucially, Monarch Butterflies depend on healthy populations of milkweed. Other butterflies depend upon larval foodplants, too. If you have an herb or vegetable garden, you may have encountered a few of the strikingly colored Black Swallowtail caterpillars. Just pick them off if there are too many, but remember they need to eat if you want butterflies. They will cause some damage, but they will not kill the plant.
Native shrubs are drought tolerant and bloom from Spring to Fall, usually in response to rain or irrigation. Butterflies of all species love them. How about a Red Bird of Paradise? Adding this to your garden will attract some of the larger, showier species. One butterfly sure to come is the Pipevine Swallowtail. This black, orange, and iridescent blue species is one of the largest and most conspicuous of Southwestern Butterflies.
Trailing Lantana is an excellent addition to your butterfly garden. This nectar source draws all kinds of butterflies, and many will often favor it over other flowers. Butterfly observers everywhere know that milkweed plants are critical to butterflies. This is especially true in the desert Southwest, where many species of milkweed occur and are native. They are a major source of nectar for butterflies of all sizes, but crucially, these plants are the major source of food for the caterpillar of the Monarch butterfly.
In 2022, the International Union for Conservation of Nature (IUCN) declared the migratory Monarch Butterfly as endangered. Monarch populations are declining due to habitat loss, eradication of the plants it depends upon, and environmental factors. Monarch numbers have declined more than 80% since the 1990’s in Central Mexico, and more than 99% since the 1980’s in coastal California!
You can help by joining Tucson Botanical Gardens’ Monarch Waystation program. To offset the loss of milkweeds and nectar sources we need to create, conserve, and protect Monarch butterfly habitats. Create a “Monarch Waystation” at home, schools, businesses, parks, zoos, nature centers, and along roadsides. Creating a Monarch Waystation can be as simple as adding milkweeds and nectar sources to your existing garden or maintaining a natural habitat with milkweeds. No effort is too small to have a positive impact.
To qualify as a registered Monarch Waystation through “Monarch Watch,” plant at least 10 milkweeds of varying species, particularly those native to Arizona. Include other host plants and nectar plants to draw a variety of other butterflies to your garden. The Southeast Pinal County Master Gardeners and Tucson Botanical Gardens always recommend native plants from a local nursey when available.