Troubleshooting
Daylily 'Mary Todd' problems — and how to fix them
Daylily 'Mary Todd' (Hemerocallis 'Mary Todd') 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.
Rust (Phakopsora hemerocallidis)
Orange-yellow pustules on leaf undersides; a newer fungal disease in many regions. Remove and bin infected foliage; do not compost. Fungicide sprays containing myclobutanil can reduce spread.
Aphids
Soft-bodied insects congregating on new growth and flower stems; dislodge with water or treat with insecticidal soap. Natural predators such as ladybirds provide good biological control.
Leaf streak
Brown or tan streaks along leaf blades caused by Aureobasidium fungus; cut back affected leaves and thin clumps for better airflow.
Slug damage
Young emerging shoots are vulnerable to slug feeding in spring; use iron phosphate-based slug pellets or diatomaceous earth around the crown.
Hemerocallis gall midge
Larvae cause distorted, swollen buds that fail to open. Remove and destroy all galled buds; do not compost. No effective chemical control for the home garden.
Prevent daylily 'mary todd' problems before they start
Most daylily 'mary todd' issues are care-mismatch, not bad luck. Dial in the basics:
Daylily 'Mary Todd' problems — FAQ
Why is my daylily 'mary todd' rust (phakopsora hemerocallidis)?
Orange-yellow pustules on leaf undersides; a newer fungal disease in many regions. Remove and bin infected foliage; do not compost. Fungicide sprays containing myclobutanil can reduce spread.
Why is my daylily 'mary todd' aphids?
Soft-bodied insects congregating on new growth and flower stems; dislodge with water or treat with insecticidal soap. Natural predators such as ladybirds provide good biological control.
Why is my daylily 'mary todd' leaf streak?
Brown or tan streaks along leaf blades caused by Aureobasidium fungus; cut back affected leaves and thin clumps for better airflow.
Why is my daylily 'mary todd' slug damage?
Young emerging shoots are vulnerable to slug feeding in spring; use iron phosphate-based slug pellets or diatomaceous earth around the crown.
Why is my daylily 'mary todd' hemerocallis gall midge?
Larvae cause distorted, swollen buds that fail to open. Remove and destroy all galled buds; do not compost. No effective chemical control for the home garden.