# Milkweed in Illinois

> 17 milkweed species are recorded in Illinois.

Source: https://milkweedusa.com/states/illinois/  
Licence: CC BY 4.0 (Milkweed USA)

## Overview

Almost all of Illinois’ original tallgrass prairie is now cropland, so its milkweed survives in railroad rights of way, cemetery prairies and roadside ditches. Those remnants hold some of the best populations of prairie milkweed and Mead’s milkweed left anywhere.

- Species recorded: 17
- USDA hardiness zones: 5a–7a
- Monarch flyway: eastern
- Best time to sow seed outdoors: late October to early December

## Species recorded in Illinois

| Common name | Scientific name | Native | Height | Bloom |
| --- | --- | --- | --- | --- |
| Swamp Milkweed | Asclepias incarnata | Yes | 3 ft–5 ft | June to September |
| Butterfly Weed | Asclepias tuberosa | Yes | 1 ft–3 ft | May to September |
| Prairie Milkweed | Asclepias sullivantii | Yes | 2 ft–4 ft | June to July |
| Purple Milkweed | Asclepias purpurascens | Yes | 2 ft–4 ft | May to July |
| Poke Milkweed | Asclepias exaltata | Yes | 3 ft–6 ft | June to July |
| Green Antelopehorn | Asclepias viridis | Yes | 1 ft–2.5 ft | April to July |
| Aquatic Milkweed | Asclepias perennis | Yes | 1 ft–3 ft | May to September |
| Common Milkweed | Asclepias syriaca | Yes | 3 ft–6 ft | June to August |
| Whorled Milkweed | Asclepias verticillata | Yes | 1 ft–2.5 ft | June to September |
| Clasping Milkweed | Asclepias amplexicaulis | Yes | 1.5 ft–3 ft | May to July |
| Fourleaf Milkweed | Asclepias quadrifolia | Yes | 1 ft–2 ft | May to June |
| White Milkweed | Asclepias variegata | Yes | 1.5 ft–3.5 ft | May to July |
| Oval-leaf Milkweed | Asclepias ovalifolia | Yes | 8 in–1.7 ft | June to July |
| Green Comet Milkweed | Asclepias viridiflora | Yes | 1 ft–3 ft | May to August |
| Tall Green Milkweed | Asclepias hirtella | Yes | 2 ft–4 ft | June to August |
| Mead’s Milkweed | Asclepias meadii | Yes | 1 ft–2 ft | May to June |
| Woolly Milkweed | Asclepias lanuginosa | Yes | 4 in–1 ft | May to June |

## How to cite

Milkweed USA. (2026). Milkweed in Illinois. https://milkweedusa.com/states/illinois/