Champaign County, Ill. (WCIA)
Milkweeds in the Garden
• In recent years, monarch butterfly populations have been in trouble for a variety of reasons, resulting in a real need for conservation
• Milkweed plants are the exclusive food source for monarch caterpillars, making them extremely important in monarch conservation
• Many Gardners have added milkweeds to their landscape in support of monarch caterpillars.
• As Gardners observe plants for monarchs, there are a variety of other insects commonly found on milkweed as well that we get a lot of questions about.
Insects on Milkweed
• Monarch caterpillars (Danaus plexippus)
• Milkweed Bugs –
o Two species of milkweed bugs feed on native milkweeds:
Large milkweed bug (Oncopeltus fasciatus)
Small milkweed bug (Lygaeus kalmia)
o Both adults and nymphs are commonly found feeding on and around seed pods
• Milkweed Tussock Moth Caterpillars (Euchaetes egle)
o Caterpillars go from hairless to tufted hairs and consume milkweed in large groups
o Hard to miss since they can devour whole plants
• Oleander Aphids (Aphis nerii)
o One of the most commonly occurring and asked about insects on milkweed
o Often feed in large clusters at the tip top of plants; rapidly reproduce, almost overnight
o Can stunt growth and deform plants
What should I do?
• All of the species we talked about are native, except oleander aphids
• Aphids are the only insect that control may be necessary
o All control measures must be carefully considered to avoid impacts to monarchs