Troubleshooting
Hoary Stock problems — and how to fix them
Hoary Stock (Matthiola incana) is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Fusarium wilt
A soil-borne fungal disease causing sudden wilting and stem blackening at the base; avoid overwatering, use fresh compost each year, and do not plant stocks in the same spot two years running.
Clubroot (Plasmodiophora brassicae)
As a Brassicaceae member, stock is susceptible to clubroot, which causes swollen, distorted roots and stunted growth; lime the soil to raise pH above 7 and rotate planting sites.
Aphids
Colonies of grey or green aphids cluster on growing tips and flower buds in spring; control with a strong jet of water or insecticidal soap, avoiding broad-spectrum insecticides that harm pollinators.
Prevent hoary stock problems before they start
Most hoary stock issues are care-mismatch, not bad luck. Dial in the basics:
Hoary Stock problems — FAQ
Why is my hoary stock fusarium wilt?
A soil-borne fungal disease causing sudden wilting and stem blackening at the base; avoid overwatering, use fresh compost each year, and do not plant stocks in the same spot two years running.
Why is my hoary stock clubroot (plasmodiophora brassicae)?
As a Brassicaceae member, stock is susceptible to clubroot, which causes swollen, distorted roots and stunted growth; lime the soil to raise pH above 7 and rotate planting sites.
Why is my hoary stock aphids?
Colonies of grey or green aphids cluster on growing tips and flower buds in spring; control with a strong jet of water or insecticidal soap, avoiding broad-spectrum insecticides that harm pollinators.