# Milkweed in Idaho

> 3 milkweed species are recorded in Idaho.

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

## Overview

Showy milkweed follows the Snake River Plain and its irrigation network across southern Idaho, forming the state’s main monarch breeding habitat. Pallid milkweed turns up on dry clay barrens in the southwest corner.

- Species recorded: 3
- USDA hardiness zones: 3a–7a
- Monarch flyway: western
- Best time to sow seed outdoors: September to November, before the ground freezes

## Species recorded in Idaho

| Common name | Scientific name | Native | Height | Bloom |
| --- | --- | --- | --- | --- |
| Showy Milkweed | Asclepias speciosa | Yes | 2 ft–5 ft | May to August |
| Narrowleaf Milkweed | Asclepias fascicularis | Yes | 2 ft–4 ft | May to September |
| Pallid Milkweed | Asclepias cryptoceras | Yes | 4 in–1 ft | April to June |

## How to cite

Milkweed USA. (2026). Milkweed in Idaho. https://milkweedusa.com/states/idaho/