# Milkweed in California

> 14 milkweed species are recorded in California.

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

## Overview

California holds more milkweed species than any other western state: narrowleaf in the Central Valley, heartleaf and California milkweed in the foothills, desert and rush milkweed in the south. Its coastal groves host the entire overwintering western monarch population. Tropical milkweed is a serious problem here and should not be planted.

- Species recorded: 14
- USDA hardiness zones: 5a–11a
- Monarch flyway: western
- Best time to sow seed outdoors: October to December, so the seed uses winter rain

## Species recorded in California

| 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 |
| Heartleaf Milkweed | Asclepias cordifolia | Yes | 1 ft–3 ft | May to July |
| California Milkweed | Asclepias californica | Yes | 1 ft–3 ft | April to July |
| Rush Milkweed | Asclepias subulata | Yes | 2 ft–6 ft | nearly year-round in frost-free areas |
| Woollypod Milkweed | Asclepias eriocarpa | Yes | 2 ft–4 ft | May to August |
| Desert Milkweed | Asclepias erosa | Yes | 2 ft–5 ft | April to September |
| Whitestem Milkweed | Asclepias albicans | Yes | 3 ft–10 ft | January to May and November to December |
| Balloon Plant | Gomphocarpus physocarpus | No | 3 ft–6 ft | May to October |
| Tropical Milkweed | Asclepias curassavica | No | 2 ft–4 ft | nearly year-round in frost-free areas |
| Woolly Milkweed | Asclepias vestita | Yes | 1 ft–3 ft | April to July |
| Giant Milkweed | Calotropis procera | No | 6 ft–12 ft | nearly year-round in frost-free areas |
| Pallid Milkweed | Asclepias cryptoceras | Yes | 4 in–1 ft | April to June |
| Serpentine Milkweed | Asclepias solanoana | Yes | 4 in–10 in | May to July |

## How to cite

Milkweed USA. (2026). Milkweed in California. https://milkweedusa.com/states/california/