Help the monarch butterfly
The population of the monarch butterfly, a North American icon, has experienced a frightening decline in the past 18 years. Rosario Monarch Preserve in Mexico, the butterflies’ winter haven, reported that in 1996 a billion monarchs covered an area of about 45 acres, but by 2014 a mere 35 million inhabited less than two acres.
Climate change in the U.S. and Canada and deforestation in Mexico are partly responsible, but a big culprit is the widespread extermination of milkweed, a plant critical to monarch reproduction. It’s the only plant on which the female lays her eggs, and thus the only food source for the newly hatched larvae.
Herbicides such as glyphosate, sold as Roundup, have allowed farmers to greatly increase crop productivity because they kill unwanted weeds, but they also kill native plants. The result is that milkweed is disappearing at an alarming rate.
What can we do? Gardeners can help by planting milkweed, but before you gasp and say, “I am NOT planting a weed in my garden!” you should know that there are several well-behaved cultivars of milkweed. Even Asclepias syriaca, the common pink milkweed, a bully in the garden, can be tamed if it’s planted snugly between other native species, or next to a retaining wall, and its rhizomes controlled.
However, you might prefer one of the non-invasive cultivars. The bright orange butterfly weed (Asclepias tuberosa) and the brilliant red swamp milkweed (Asclepias incarnata) are wonderful options. Unlike their aggressive cousin, they don’t spread by rhizomes but by seed. Swamp milkweed prefers sun and grows in any type of soil. Butterfly weed likes full sun but will tolerate a bit of shade. It prefers medium to dry sandy soil, good news for those of us in Applewood Acres.
The stunning purple milkweed (Asclepias purpurascens) is also non invasive. Its rich red-purple flower looks similar in shape to the common milkweed. It prefers more shade and moisture than those already mentioned, but with deep regular watering it does well in full sun.
David Suzuki, Canada`s best-known environmentalist, has been hard at work raising awareness of the monarch crisis. In April 2014 the David Suzuki Foundation sold milkweed plants for $5 each through their online store www.davidsuzuki.org/gotmilkweed. The program was a huge success and was repeated in 2015.
Plants can also be purchased at both Humber Nurseries and Sheridan Nurseries.
Milkweed seeds are available through Miriam Goldberger’s website www.wildflowerfarm.com and bare root plants can be bought at Veseys, www.veseys.com. Check your local garden centre to see if they will be carrying milkweed in the spring.
Another reason to plant milkweed is that it attracts a host of other creatures, such as dragonflies, honeybees and many birds. It’s a sound ecological choice for the modern-day gardener if there ever was one.