Monarch Butterfly gardening is for the hopeful and the frugal in each of us. All it took for me was a single milkweed plant, a single caterpillar and I was enamored. Now I’m downright evangelical.
The purpose of this article is to share what I’ve learned about establishing a monarch butterfly habitat, concentrating on what didn’t catch my eye in the rich information base that already exists. I started butterfly gardening just a year ago, putting a 3" tropical milkweed (Asclepias curassavica) pot on our driveway and bingo, within a week a caterpillar got me at hello. It’s likely a miniscule egg was on that milkweed already and hatched after I received the plant from a friend. The hungry caterpillar munched all the leaves reducing the plant to stick stems and off I went on an urgent mission to buy a couple more plants. Soon, a couple other monarchs fluttered around and there were caterpillars all over the two plants. Time to get serious. I had a delightful responsibility on my hands.
First, the milkweed, the host plant for the Monarch. There are 100+ varieties in the milkweed family; the most common and easiest to grow in SoCal is tropical milkweed, Asclepias curassavica. It grows quickly and from seed can easily host monarch eggs during the same season. It’s forgiving, has lovely orange/yellow/red flowers. I germinated 100+ plants in our yard during one season – direct seeded, burlap cover to retain moisture, and got terrific results. You shouldn’t need to buy more than a plant but if you do, don’t trust the Asclepias labeling at the nurseries. Wash off those plants as they may have been sprayed with a solution that kills caterpillars. I’ve learned the monarchs gravitate to the smaller plants. All the monarch needs is a leaf big enough to support its weight (0.5 grams) for that egg-laying moment. Plus, the females may lay 200 eggs a day so they are busy and they diversify where they lay their eggs. There is no need for a flowering plant for the egg-caterpillar host stage.
I’ve grown and repotted hundreds of Asclepias. I cut them back mid-January to 6" and they came back gloriously this year. It’s important to cut them back to prevent the spread of diseases that can build up on the plants if they’re used by monarchs over multiple generations. Water once a week once established. I’m trying to rear some A. physocarpa (goose plants with pods that will be golf ball size), A. fascicularis, and A. eriocarpa and failed at A. tuberosa and A. californica. It’s best to have plants that are native to the local area.
Next, the nectar plants. Once a monarch is a butterfly, you need nectar plants so they hang around. Good chance there’s a lot of those in your neighborhood, but you can always provide more of a feast with buddlejas, calendula, lantana, and even flowering milkweed. That list is endless.
Monarch eggs become caterpillars and once they have shed their skins five times and grown plump, they generally crawl away from milkweed to some other plant or surface to pupate into a chrysalis. I’ve read they can go 40 feet, and in our yard there were chrysalises on the iris, fuchsia, plectranthus, geraniums, sides of palm trees, hose holders, spigots, brick chimney, roof eaves, with the bulk on the teak patio table and chairs. Monarch caterpillars do not eat your veggies, roses or anything other than milkweed.
Realtors always say “Location, location, location!” It’s true for a habitat. I’ve decided to not plant milkweed directly beside a sidewalk because as they start hatching and wandering, the risks of them getting squished by a bicycle or walker are pretty high, but if your only choice is near a walking path, don’t be deterred by this potential issue. Monarchs need our help. If you have a sunny area near a fence, that’s perfect. If you want to get compulsive like I did, in the fall go get sticks and poke them around the yard – they will climb up and down them and pupate there. I put pots of calendula everywhere so I can relocate them from the front yard, which is prime hunting territory for a young energetic kitty, to the backyard, which is a more serene flight path.
A monarch habitat is within reach of people of all ages. It’s a great family project and is especially fun for seniors –- put the plants outside a window, forget to water them for a while, by that time it’s in Mother Nature’s hands to a large degree anyway. Get a $10 magnifying glass at Rite Aid (the kind with a handle and a 5X or 10X little circle lens in the corner and a hand mirror (to view eggs and caterpillars on the undersides of the leaves without disturbing them) and you’re in business.
Starting in early June, I noticed a lot of European paper wasps in our yard. Even though the exterminator had removed a nest a month before, because he came during the afternoon, it’s unlikely he got many of them as they were out foraging. Remove nests in the early morning. Wasps are monarch predators and I did notice them flying all around the milkweed, likely grabbing eggs and caterpillars, both protein sources, for their own young. I tried retail Rescue traps, homemade traps with sugary solution and others with raw meat, but had no interested wasps. I ended up calling the local Vector Control folks for advice, and to my surprise, learned that it’s a county service and we can call to report stinging insects (and other stuff) and they will come out free to inspect the exterior of structures and remove nests.
You’ll probably end up with bright yellow oleander aphids at some point. Take out that magnifying glass and you’ll see why they are called “dancing yellow aphids”. They cluster at the top of the plant first then spread. They don’t seem to move to other plants but they can multiply fast. They can weaken the plant and if you’re lucky, you’ll have some ladybugs to help manage that. Squishing them is a way to eliminate them. Soapy water was not impactful, plus be careful about the caterpillars with any soaps. Also remember to be careful with milkweed -- the milky sap is an irritant so don’t rub your eyes and wash your hands, many plants are poisonous, we sometimes can forget that.
The Western Monarchs don’t migrate to Mexico, at least most of them! Honest! There have been a few sightings of monarchs tagged in Arizona that have ended up in Mexico, but for the most part, ‘our’ monarchs migrate to several locations along the coast of California. I’ll leave the science to the references below.
Monarchs don’t know where your property line ends and the neighbor’s begins. Help others in your neighborhood get started. You’ll be amazed how captivating and fun it is to wonder if and when they will arrive. It’s July and although I have been blessed with resident monarchs, I’m seeing the lovely fluttering tattered wings of others who are on their way somewhere else, and I believe in the magic that they are the same ones that passed through towards the coast at an earlier time.
- - Monarch Larva Monitoring Project (University of Minnesota. My most favorite. I joined their Citizen Scientist program. I count Larvae and Aphids. See my statistics from the Main Menu -> Results & Findings -> Monitoring Data & Graphs -> “click” on the CA map -> Los Angeles, Wade St Mar Vista. Great way to learn and give back. Takes 2-3 hrs/wk.
- - Monarch Watch (University of Kansas)
- - http://www.fs.fed.us/monarchbutterfly/migration/ U.S. government site
- - http://www.naba.org/chapters/nabala/gardens.htm (North American Butterfly Association)
- - http://www.mybutterflyguide.com/Butterfly_Guide_Home_Page.html (A teacher’s site, simple and engaging)
- - http://www.butterflyencounters.com (Photos of various milkweed species)
- - http://www.monarchprogram.org/ (Encinitas Monarch Program)
Happy to help if I can -- I live in Mar Vista, CA and have A. curassavica seeds and seedlings to share, and soon seeds from the other varieties noted above. I'm email@example.com.