(Jefferson City) – The sight of a beautiful orange and black monarch butterfly in Missouri is likely to be less common this year due to a number of factors, but you may be able to help the ones that do arrive in the Show-Me State.
A January 2014 report from their overwintering forest areas in Mexico indicated that only 1.65 acres were occupied by monarchs this winter, marking the third straight year of steep declines. A number of factors have contributed to the decline of the monarch population in recent years: Unusually hot weather in the spring of 2012, unusually cold weather last spring, and the loss of habitat throughout the Great Plains have combined to create hardships for the insects. Higher grain prices in recent years have resulted in more land being cultivated for crops and more weed-free farming techniques have reduced the number of milkweed plants in most agricultural fields. Several milkweed species are still common in Missouri, but in highly agricultural areas the plants can be too scarce to support migrating monarchs.
Monarchs lay their eggs on milkweed plants, of which Missouri has 17 native species. The entire life cycle of the first three generations lasts 6 to 8 weeks each and four generations occur each year. The adult butterflies of the fourth generation migrate to Mexico and live until they lay eggs on their way back north the following spring. So the monarchs that you see moving south in the fall are four generations removed from the ones that headed north in the spring.
Planting milkweeds, especially in areas where they are currently scarce, can help monarchs be more successful in rearing new generations. Milkweeds are appropriate for use in home landscape plantings and several species are popularly used, especially by gardeners who enjoy helping monarch butterflies. Several milkweed varieties grow well in Missouri and range from 2 to 6 feet tall in a variety of colors.
Nurseries that sell native plants often sell seeds and potted plants of those species. For a list of suppliers, see the Resource Guide on the Missouri Prairie Foundation’s Grow Native website at this link: grownative.org/resource-guide/.