Troubleshooting
Dahlia 'Soda Fountain' problems — and how to fix them
Dahlia 'Soda Fountain' (Dahlia 'Soda Fountain') 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
Appears as a white film on older leaves. Improve spacing, avoid wetting foliage, and apply a potassium bicarbonate spray at early onset.
Botrytis (grey mould)
Fuzzy grey mould on stems and petals in cool, damp weather. Remove affected tissue promptly and improve air circulation.
Earwig damage
Flowers develop irregular holes. Set earwig traps (damp newspaper tubes) near the base of plants each evening.
Dahlia mosaic virus
Yellowing, mosaic patterning, and stunted growth. Transmitted by aphids. Remove and destroy infected plants; control aphids to reduce spread.
Tuber rot in storage
Caused by excessive moisture during winter storage. Cure tubers in a dry, airy spot before storing in barely moist vermiculite at 5-10°C.
Prevent dahlia 'soda fountain' problems before they start
Most dahlia 'soda fountain' issues are care-mismatch, not bad luck. Dial in the basics:
Dahlia 'Soda Fountain' problems — FAQ
Why is my dahlia 'soda fountain' powdery mildew?
Appears as a white film on older leaves. Improve spacing, avoid wetting foliage, and apply a potassium bicarbonate spray at early onset.
Why is my dahlia 'soda fountain' botrytis (grey mould)?
Fuzzy grey mould on stems and petals in cool, damp weather. Remove affected tissue promptly and improve air circulation.
Why is my dahlia 'soda fountain' earwig damage?
Flowers develop irregular holes. Set earwig traps (damp newspaper tubes) near the base of plants each evening.
Why is my dahlia 'soda fountain' dahlia mosaic virus?
Yellowing, mosaic patterning, and stunted growth. Transmitted by aphids. Remove and destroy infected plants; control aphids to reduce spread.
Why is my dahlia 'soda fountain' tuber rot in storage?
Caused by excessive moisture during winter storage. Cure tubers in a dry, airy spot before storing in barely moist vermiculite at 5-10°C.