Oh, how I love to raise Monarchs! Those striped larvae that transform themselves into lovely butterflies fascinate me. Watching them munch away on Milkweed generates great joy and anticipation.
I’ve observed Monarch (Danaus plexippus) caterpillars morph into chrysalises countless times and am always mesmerized. It brings such pleasure to release butterflies that I’ve raised into my garden, especially when they linger.
Stages of Monarch butterflies from caterpillar to adult. Top Row (left to right): Fifth-instar caterpillar traveling on a wire to find a good place to pupate. Caterpillar in the “J” position. Newly-formed chrysalis, still showing wrinkles. Middle Row (l-r): Completed chrysalis, also called a pupa. Chrysalis with nearly transparent cuticle signaling the eminent eclosure (emergence) of the adult butterfly. Freshly-eclosed Monarch hanging on to the remnant of its chrysalis. Bottom Row (l-r): Monarch filling its wings with abdominal fluid before they harden. Fully-fledged adult Monarch nectaring on a yellow variety of Tropical Milkweed.
If you want to raise healthy Monarchs, you have to have Milkweed (Asclepias spp.) and lots of it! Anyone who has ever raised Monarch butterflies has probably, at one point or another, run out of Milkweed. I’ve driven 30 miles to the nearest reliable supplier to replenish Milkweed for hungry caterpillars. It’s astonishing how much these caterpillars devour during their last two instars.
Monarch caterpillars that have eaten their Milkweed cuttings down to the bare stems.
The best way to get Milkweed is to grow it yourself. You have more control over the quantity and quality of your plants. That said, some species of Milkweed can be a chore to grow.
Tropical Milkweed (Asclepias curassavica), on the other hand, is easy to grow from seed or propagate from cuttings. (Tropical Milkweed is also known as Scarlet Milkweed, Mexican Butterfly Weed, Bloodflower, Redhead, Cotton Bush and Wild Ipecacuanha.) To obtain seeds for Tropical Milkweed, Click Here .
While Tropical Milkweed readily grows from seeds, if you already have stock in your garden, growing it from cuttings is the easiest and fastest way to expand the number of milkweed plants needed to feed your hungry caterpillars.
Tropical Milkweed propagation (left to right): Stem cuttings placed in potting soil. Plants after four weeks. Full-size, blooming plants after just eight weeks.
Once the Monarch caterpillars have stripped the Milkweed plant of all its leaves, cut the stems by pruning the plant and leaving about 5-6 inches (12-15 cm) of stems on the plant. It is painful, I know. But, this is actually a very good way to stimulate more growth and fullness of the plant.
Many Monarch experts also believe that by cutting back Milkweed, of any variety, it can reduce OE (Ophryocystis elektroscirrha) infections in Monarch butterfly populations. OE is a naturally-occurring protozoan parasite that can infect Monarch and Queen (Danaus gilippus) butterflies to the point of harming its hosts.
Even if you do not want to propagate new plants from stem cuttings, Tropical Milkweed should be pruned back on occasion, as it gets too “leggy” and ineffective at producing leaves and flowers. Also, I find that pruning Milkweed helps control and even eliminate Aphids (Aphididae spp.).
These four Tropical Milkweed plants have just been trimmed. Pruning will stimulate growth, help eliminate OE spores, and create bushier branches with more flowers. The two small Tropical Milkweed plants at the top of the photo were grown from seed.
If you have potting soil and containers available, simply place the stems directly into the potting soil. Keep the soil moist until you start to see leaves sprouting from the nodes (the bumps on the stems where leaves used to be). At the same time, roots will be growing from the nodes underground. These are 4-inch (10 cm) nursery pots. Click Here to find similar pots.
You can also place the stem cuttings in the water and soak them until they grow roots. The cuttings will grow leaves within a few days and roots in a week or two. However, you can transfer them directly to potting soil anytime. Just remember to keep the soil moist where you have planted the new stem cuttings. You can also speed up the growth by adding Miracle-Gro®, mixed half-strength each time you water. Click Here for Miracle-Gro®. Either dry or liquid works well.
Budding stems of Tropical Milkweed cuttings sitting in water and placed in a window for light. Don’t let the cuttings dry out.
I grow most of my Tropical Milkweed in pots. After two years, I retire them to a garden bed, removing them from their pots and trimming their roots lightly, because they can become root-bound. One season, I grew 200 plants from cuttings. It was a lot of work but I was able to feed hundreds of Monarch caterpillars!
These Tropical Milkweed plants are growing in a screened-in canopy tent to prevent Monarchs and Queens from laying eggs. In the tent, I can also regulate how much water they get and can better control pests such as OE and Aphids. If these tents aren’t available locally, you can Order Here.
If you have a love affair with Monarchs and Milkweed like I do. There’s no cure. Accept it. Embrace it. Feed the passion and reap the joy!