Got Milkweed?
By Loree Bryer (September 2010)
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.
References
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 lor...@ca.rr.com.