In recent years, Monarch butterfly populations have been on the decline. This is a result of habitat loss due to pesticide use and deforestation, parasites crippling populations, and life cycle changes due to climate change. You can help keep these beloved pollinators safe and happy by rearing butterflies in a safe area free of predators, or by planting native wildflowers in your garden.
When raising butterflies there are three main tenants to follow:
- Replicate natural conditions as much as possible
- Handle the butterflies and caterpillars as little as possible
- Release the hatched butterflies after one hour
How to set up a box:
For this, any clear plastic box works. You need to poke small holes onto the top of the box so the caterpillars can breathe. Leave a damp paper towel at the bottom of the box and replace it when the box gets dirty (for example from caterpillar poop). Place the milkweed leaves on top of the paper towels and make sure to add more if the leaves ever run low (caterpillars eat A LOT).
The caterpillars will crawl to the top of the box when they are ready to form a cocoon. Beware of caterpillars that reach this stage at the same time because they will sometimes start fighting for their favorite spot. If this happens, just be sure to separate them.
Monarchs only lay eggs on milkweed because the plant contains all the necessary nutrient for their growth. Additionally, caterpillars eat milkweed because the plant creates a toxic latex that then makes the fully-grown butterfly poisonous to predators. The fully-grown butterflies also can rely on the milkweed flowers for nectar!
Three common types of milkweed are Common milkweed (A. syriaca), Swamp milkweed (A. incarnata), and Butterfly weed (A. tuberosa).
Monarchs seem to most prefer Common milkweed and Swamp milkweed because their leaves are softer than that of Butterfly weed. However, between the two, Swamp milkweed is more ornamental and less invasive so you may prefer to use that in your garden.
Some people suggest to cut back the milkweed in June so that the new-grown leaves are fresh and soft for butterfly reproduction in the July.
Monarch reproduction peaks in late summer. You’ll be able to start collecting eggs off of the Milkweed in July, and you’ll likely keep finding them until mid-August.
You can plant milkweed alongside asters, black-eyes susans, blazing stars, snapdragons, zinnias, goldenrod, lavendar, and lilac and hollyhock to create a beautiful butterfly garden.
Egg to Caterpillar
In this picture you can see the progression of the butterfly egg into a large caterpillar. It takes about 4 days for the egg to hatch and then it stays in the caterpillar stage for about 10 to 14 days.
Chrysalis to Butterfly
The Chrysalis phase lasts for about 8 to 15 days. During the last few days you can see the orange and black colors of the butterfly wings in the Chrysalis. As the butterfly emerges, it pumps liquid into its wings. The butterfly will hang upside down as the fluid is dispersed and as the wings dry off. Do not try to release or move the butterfly until its wings are dry. You can tell the butterfly is ready when it starts moving around the box.
Identifying Butterfly Gender
→ Male butterflies (on the right) have thinner black veins and they have small matching spots on their lower wings.
→ Female butterflies (on the left) have thicker black veins and no spots.
Releasing the Butterfly
Sometimes when you release the butterfly, it will fly off by itself as soon as you open the box. Other times it will cling onto the lid. In those moments, you can put your finger near the butterfly’s legs and lift it up with your finger, and then deposit it on the nearest plant. Be sure to NEVER touch the butterfly’s wings! Their wings are incredibly delicate, and any touch can debilitate the butterfly for life.