Question
I have 2 spirea bushes that are at least 20 years old. They have grown and blossomed nice the past couple years (i have only been caring for the for 3 years) Last year the back half of one started to dye off and never grew leaves. I went to trim back the dead area's and noticed that now my other bush has dead spots. Now both of my bushes look like they received bad haircuts. What is killing these bushes and what can I do to save them?

Answer
Dear Allyson,

Hello, I'm sorry to great you with your Spirea problem. I've had a few occasions like this and it always seems when the leaves and branches are declining it's "Fire Blight"

Fire Blight is a bacterial disease is spread by insects and rain. It is one of the most destructive diseases of some spireas, destroying leaves and limbs.

To solve this problem I would recommend you prune out infected branches, cutting at healthy tissue well below blighted areas. Spray shrubs with a streptomycin or other such product to protect blossoms. Do not over fertilize, because excess nitrogen makes the shrub more blight-prone. This disease is rarely serious unless the spirea is planted near pears, apples or hawthorns which are also susceptible to it.

Spireas also suffer from powdery mildew. A general garden fungicide will take care of the problem. Make sure you dispose of the fallen leaves with the bacteria to make sure the bacteria is not still around to re-infect your Spirea.

As a last piece of advice, read the directions on the fungicidal product you use, most likely you will have to use multiple applications to fix your problem.

Happy Gardening,

Coach Dave
Garden Expert for The Home Depot