monarch butterfly on milkweed plant

How To Grow Milkweed For Monarch Butterflies

Never judge a plant by its name. That is absolutely true of this wildflower, which isn’t truly a weed at all. The monarch butterfly’s solitary host plant is this hardy native of North American fields, marshes, and grasslands. Milkweed (Asclepias) receives its name from the sticky white fluid that oozes from its injured leaves. This herbaceous perennial has over 100 species endemic to the United States and Canada. 

In most parts of the country, three varieties of milkweed are suitable all-around selections for gardens: Swamp milkweed (A. incarnata), Common milkweed (A. syriaca), and Butterfly weed (A. tuberosa). Swamp milkweed and butterfly weed are both extremely decorative plants with several varieties. 

Growing Milkweed

Milkweed’s tiny, star-shaped blossoms are well built for pollination. Milkweed blooms can be yellow, green, purple, pink, or orange depending on the plant. The huge seed pods that form from the fertilized blooms are very nicely formed. These skilled self-sowers break open in the fall, releasing hundreds of seeds.

Here are some brief facts about the popular aesthetic plant:

  • Latin name: Asclepias spp.
  • Other names: Butterfly flower, silkweed
  • Native to: North America
  • Invasiveness: No
  • Tenderness: Herbaceous perennial
  • Sun: Full sun
  • Water: As required
  • Soil: Any well-drained soil; tolerates clay soil and poor, dry conditions
  • Hardiness zone: Zones 3 through 9
  • When to plant: Fall
  • Spacing: 18 inches
  • Plant height: 2 to 4 ft. 
  • Bloom period: Summer to early fall
  • Time to maturity: 1 year
  • Container friendly: Yes
  • Fertilizer: Not required
  • Toxicity: Toxic to humans and animals
  • Deer resistant: Yes
  • Pest resistant: No

The majority of milkweeds demand full sun (at least 6 to 8 hours a day). Because they rapidly self-seed, put them in an area of the garden in which you can effectively manage their expansion, such as at the rear of the boundary or in a corner. A wind-sheltered location will also assist to restrict the distribution of seeds while also creating a more welcoming environment for butterflies. It’s worth noting that milkweeds have a taproot and are difficult to transplant. If you’re starting from seed, spread the seeds outside in the autumn to allow them the time to stratify, which will increase spring germination and assure a beautiful flower show the following year.


Except in the driest of conditions, ordinary milkweed does not require irrigation. Water the plants deeply, giving them one to two inches of water, and then wait till the top layer of soil is dried before watering again. Overwatering ordinary milkweed can cause a deadly fungus.


The common milkweed loves direct sunshine. It thrives in open areas with six to eight hours of sunshine every day.


This plant prefers a well-drained, dry to medium ordinary soil. It can withstand dry weather, barren soil, and rocky terrain. Milkweed’s preferred soil type is typically determined by its natural environment. The majority of cultivars are fairly forgiving and will thrive in regular garden soil. The exception is swamp milkweed, which requires damp, humus-rich soil.


Fertilizing common milkweed plants is unnecessary. Poor soils are tolerated by common milkweed.


Milkweeds are not listed as noxious weeds by the federal government or any state in the United States. In reality, at least five species are recognized as endangered by the state or federal government (Borders, LeeMäder 2014). Some milkweed species, such as common milkweed (Asclepias syriaca), have a reputation for being “weedy” because they are more aggressive in garden settings or disturbed regions. If you are concerned about the proliferation of milkweed in your region, select species that are native to your area and avoid species that are particularly adept at vegetative, clonal reproduction, or are prolific seed producers.  

Growing Milkweed In Containers

Common milkweed seeds self-spread just before the winter seasons arrive, allowing them to naturally undergo cold stratification. In the fall, you may spread seeds directly in the ground to allow them to go through this process, putting them about an inch deep in the soil.

Remember that the cold stratification method to boost germination rate takes 30 days when starting common milkweed seeds indoors, so start that process in March.

Care & Tips

Plant the seeds in a smooth, clump-free soil bed worked to a fine texture using a rake or rototiller to guarantee effective germination. After you’ve sowed the seeds, compress them (but don’t cover them) into the soil to ensure proper soil-to-seed contact. Keep the sowing bed wet until the seedlings emerge. As your plants grow, trim out those that are too close together so they don’t compete for sunlight and soil nutrients.

Common Problems

Milkweed bugs (which don’t cause much harm), aphids, spider mites, whiteflies, thrips, scale insects, and leaf miners are all attracted to common milkweed. Scrape off the offenders using a hose, a bottle, or your fingernails. Snails and slugs enjoy young fragile milkweed plants as well. Snail bait works effectively and does not damage monarch butterflies, although the snail problem fades as the plants mature.

Keep an eye out for fungal issues including verticillium wilt, leaf spots, and root rot. Trim diseased leaves and branches with leaf spots, but the other two fungal problems may be more difficult to solve.

Propagating Milkweed

Many milkweed species may be cultivated from root or rhizome cuttings or from seed. When the plant is dormant and has higher energy reserves, take the cuttings in late fall or early spring. When the weather warms, new sprouts will emerge from the cuttings and will frequently produce blooms in the first year.

Wildlife attracted by Milkweed

Aside from monarch butterflies, honey bees, bumblebees, hummingbirds, and a variety of other butterflies are regular visitors. Learn more about pollinator-friendly perennials. Milkweed serves as a food source as well as a host plant for monarch butterfly eggs placed on the underside of the leaves. After hatching, the larvae eat on the leaves but do not harm the plant in any way. As a result of the poisonous substances in the milkweed plant sap, predators avoid both caterpillars and adult butterflies.

The History Of Milkweed

Milkweed plants were utilized by Native Americans for a variety of purposes, including food and medicine. The leaves of the plant were cooked or stewed in the same way as spinach or kale were. Its blossoms were picked while they were still green and cooked like broccoli.

Uses For Milkweed

The plant has always been highly valuable because of its medical benefits. Lifejackets are occasionally filled with the silky substance linked to its many seeds. Seeds are housed in a visually appealing pod that explodes, sending seeds soaring through the air, carried by the wind. When growing milkweed plants, remove seed pods for this reason.

Monarch butterflies and their host plants, milkweeds, have come to represent a broken relationship between humans and nature – as well as a chance to repair it. One of the key reasons monarchs are in difficulty today is the eradication of milkweed in agricultural regions as well as urban and residential environments.

The good news is that growing milkweed is one of the simplest ways that every one of us can help monarch butterflies. There are many dozen species of this wildflower endemic to North America, therefore no matter where you reside, you will find at least one milkweed species. Except for monarch butterflies, the milkweed leaves and milk-like fluid within are toxic.

Mayukh Saha
Freelance Writer
Mayukh is a Content Marketer and Social Media Manager with over 5 years of experience in the industry. Mayukh believes in the power of content; how it can positively impact lives, scale businesses and touch people. In his spare time Mayukh likes to read about latest tech trends and loves to travel in the nature. You can reach him at [email protected].