Troubleshooting
Dahlia 'El Trasno' problems — and how to fix them
Dahlia 'El Trasno' (Dahlia 'El Trasno') 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.
Powdery mildew
Very common in warm, dry summers. Keep plants well watered and spaced for airflow; apply a sulphur-based or potassium bicarbonate fungicide.
Earwigs
Chew flower petals at night, spoiling the collerette display. Trap in inverted pots stuffed with straw placed on stakes near the plant.
Aphids
Colonise new shoots and bud bases. Control with regular insecticidal soap applications; monitor for virus signs (mottled foliage).
Slugs
Damage emerging shoots in spring. Use iron phosphate pellets or set beer traps near planting holes.
Tuber rot in wet winters
Leaving tubers in ground in cold, wet regions leads to rot. Lift after the first frost, dry for several days, and store in a cool (5-10°C), frost-free place.
Prevent dahlia 'el trasno' problems before they start
Most dahlia 'el trasno' issues are care-mismatch, not bad luck. Dial in the basics:
Dahlia 'El Trasno' problems — FAQ
Why is my dahlia 'el trasno' powdery mildew?
Very common in warm, dry summers. Keep plants well watered and spaced for airflow; apply a sulphur-based or potassium bicarbonate fungicide.
Why is my dahlia 'el trasno' earwigs?
Chew flower petals at night, spoiling the collerette display. Trap in inverted pots stuffed with straw placed on stakes near the plant.
Why is my dahlia 'el trasno' aphids?
Colonise new shoots and bud bases. Control with regular insecticidal soap applications; monitor for virus signs (mottled foliage).
Why is my dahlia 'el trasno' slugs?
Damage emerging shoots in spring. Use iron phosphate pellets or set beer traps near planting holes.
Why is my dahlia 'el trasno' tuber rot in wet winters?
Leaving tubers in ground in cold, wet regions leads to rot. Lift after the first frost, dry for several days, and store in a cool (5-10°C), frost-free place.