

1. Do provide more space than a jar.
While it used to be commonplace for Monarch caterpillars to be raised in jars, we’ve since learned more about their needs. More space equals bigger caterpillars, and bigger caterpillars equal bigger monarchs. Bigger monarchs are more likely to survive in the wild, especially if they’re amongst the late summer butterflies to migrate to the fir forests of Mexico. Fortunately, there are a lot of inexpensive options for butterfly tents. You’ll need two separate spaces – one for developing caterpillars, and one for butterflies. Mixing the two increases the risk that your caterpillars will contract a dangerous parasite. For more about that, read on!

Getting outside time!
2. Do keep their habitat clean.
Raising monarchs isn’t rocket science. If you follow basic principles of cleanliness, your monarchs’ survival rate is likely to reach 80-95%, far exceeding the meager 2-10% of monarchs that survive to become butterflies in the wild. It’s important to remove the caterpillars’ poop (called frass) from their dwelling at least once a day. Otherwise, you may expose your caterpillars to ophryocystis elektroscirrha (OE), a debilitating protozoan parasite that infects monarchs.


Chrysalis with soon-to-emerge butterfly.
4. Don’t raise monarchs if you don’t have access to milkweed and nectar flowers.
You’ll need a lot of food for caterpillars, and that means a reliable source of pesticide-free milkweed. Female butterflies will only lay their eggs on milkweed; there are over 100 species, so know which ones do well in your particular area. The Very Hungry Caterpillar book by Eric Carle was no exaggeration! One monarch caterpillar can eat an entire milkweed plant in the 10-14 days before it turns into a chrysalis. Don’t forget about adult butterflies, too. When you release your monarchs, they will want nectar-producing flowers.
5. Don’t raise monarchs completely inside.
Monarchs are being studied all the time. While yet inconclusive, current research indicates that monarchs raised without the normal day/night cycles and exposure to varying temperatures may not migrate as well as monarchs raised in the wild. That said, eggs, caterpillars, chrysalides, and butterflies shouldn’t be left in the direct, hot sun where they can overheat and die. So move your tents around your yard as needed, or keep them in a three-season porch.
