Troubleshooting
Mexican Sage problems — and how to fix them
Mexican Sage (Salvia mexicana) is generally low-drama, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Frost dieback
Above-ground growth is killed by frosts around -3 °C; protect the crown with a deep mulch of bark or straw and cut back dead stems to just above ground level in early spring.
Whitefly
Persistent colonies of whitefly can build up on the undersides of the large leaves, particularly in enclosed or polytunnel conditions; yellow sticky traps and biological controls (Encarsia formosa) are effective.
Prevent mexican sage problems before they start
Most mexican sage issues are care-mismatch, not bad luck. Dial in the basics:
Mexican Sage problems — FAQ
Why is my mexican sage frost dieback?
Above-ground growth is killed by frosts around -3 °C; protect the crown with a deep mulch of bark or straw and cut back dead stems to just above ground level in early spring.
Why is my mexican sage whitefly?
Persistent colonies of whitefly can build up on the undersides of the large leaves, particularly in enclosed or polytunnel conditions; yellow sticky traps and biological controls (Encarsia formosa) are effective.