Milkweed and aphids, they just go hand in hand. If you’ve brought milkweed into your gardens to help support the Monarch population, chances are, you’ve had to put up with aphids. And having to put up with them is really all you can do sometimes. These little, yellow insects converge under the leaves and line themselves up the stems, making your milkweed look like a super highway crammed with little yellow taxi cabs. Aphids can make your milkweed look a sickly. They pierce the plant and suck its juices. If you have a ton of aphids they’ll be secreting their sticky honeydew all over the leaves of your milkweed. This thin, sticky layer coats the leaves of milkweed, robbing it of its ability to absorb essential nutrients.
So what’s a Monarch butterfly lover to do? You can’t spray your milkweed with any type of insecticide. Insecticides are not selective. Any insecticide, even milder forms like insecticidal soaps, will cause harm or death to your Monarch eggs and caterpillars. You can squash the little boogers when you just have a few, but since aphids clone themselves at a rapid pace, an infestation can quickly grow out of control.
A blast of water from the hose knocks the aphids off and cleans the leaves free of the honeydew layer; BUT use caution and inspect your leaves before doing so. That hard blast of water could dislodge any Monarch eggs or larvae that are hidden on the bottoms of your leaves too! They are held on a little stronger, but nevertheless, thoroughly inspect your milkweed and rescue any eggs or caterpillars. Move them onto an uninfected plant, or to a protected location, like a butterfly pavilion (we have these at Rainbow Gardens).
If you can relax a bit and let nature take its course, you just might find that you become a big fan of natural, biological control. Beneficial insects like ladybugs, ladybug larvae, lacewings, and lacewing larvae have voracious appetites and aphids are their favorite meal.
Every fall, just as the milkweed flowers are popping in preparation for the Monarchs migration, the aphids come a’marching. But also, just when the milkweed looks like it might be meeting its demise, other inhabitants start moving in to clean it up. Lacewing eggs are laid and hatched, and the larvae start in on the aphids. Before you know it, your milkweed can be the shining star of your butterfly garden again. *A note about ladybugs and lacewing larvae. Although they are super beneficial and a great destroyer of aphids, during their feeding frenzy, Monarch eggs can get eaten too. Observe and inspect your milkweed often so you can rescue the eggs and baby caterpillars from any possible harm. More on Lacewings from my personal experience at a past Happy Gardener blog if you are interested….“Move Over LadyBugs, There’s A New Aphid Eater In Town”.
(Lacewing eggs look like this hanging from the bottom of the leaves of milkweed.)
(Now the aphids have no clue as to what lies BENEATH! Lacewing larvae!)
So what’s the take away here really? Catch your aphids early and you won’t have to stress as much. Also, don;t stress so much. Nature has its way of fixing things for you. Keep planting milkweed, so you don’t miss out on the Monarch butterflies coming to your gardens. If you find that the milkweed at the nurseries has aphids, you definitely know the plants are safe and haven’t been treated with any chemicals. We NEVER treat our milkweed at Rainbow Gardens so your Monarch butterflies have a safe host plant to lay their eggs, and a safe food source to load up on much-needed fuel.The Monarchs are on their way, and they would love to come visit you!
Come learn more about Monarchs at our seminar featuring Drake White at our Bandera location, October 27th, 10AM
The Happy Gardener