Expert: Long Island Gardener - 8/1/2006

Question
My Dahlia's arent doing so well this year.  I have buds but they are real small and they look like they are dying off even before they bloom.. It doesnt even look like the bulbs are going to open, they're too tiny.  I live in Ohio.  I never had this problem before. Can something be getting to them?  Thanks for your help..

Answer
Mites around this time of year can wreck a garden in no time flat, without warning, almost invisibly.  I'd like to know if the leaves look ok or if they are mottled or striped - which would be one symptom of a possible viral disease.

In extreme heat, Dahlias can sometimes stop blooming, or at least bloom less than usual.  You can help them by not letting them dry out.  If this is at the root of your Dahlia problems, it will clear itself up as cooler weather arrives.

Watering too little and letting your Dahlias dry out is another possible explanation here.  Remember, Dahlias need to be kept watered during active growth.  Don't make them wilt before you water them.  And always water in the morning, to minimize risk of disease.

Around this time, an insect called the Corn Borer begins to show up on Dahlias, feasting on buds and flowers; as it settles in, the Borer burrows down into the inside of your Dahlia stems. Plants wilt from the stem attack. BT (Bacillus thuringiensis) sprayed on Dahlia leaves is a surefire way to eradicate them without turning your garden into a superfund site.  Borers eat the BT bacteria, get a fatal disease, and die a few days later. See any unexplained wilting in those afflicted Dahlias?

Please get back to me about these symptoms and other red flags.  Dahlia season is approaching its height and we should all be enjoying our Dahlias now.