Question
I have several rose plants/bushes, in two different locations, all with black spot.  I've tried spraying them several times over the last two years with "commercial" stuff as well as with the baking soda concoction "home" remedy to no avail.  I have 3 that I think are climbing and 3 (or 4) plants that aren't climbing; I don't know exactly what variety of roses they are, they were here when we moved in.  How far back can I prune them to help get the black spot under control without killing them all together (which is my husbands answer to the problem)?

Answer
Hi Julie,

Not to start any domestic trouble but do not cut the bushes back.  

If you do not mind spraying, you can use Honor Guard and Manzate.   These are two chemicals that kill and prevent blackspot.  You can find them at www.rosemaina.com   Look at what they offer for fungus and what fits their budget and time.  

The plants need as much cane or branches to leaf back out on.  Pruning them only weakens them since they are only defoliated from black spot.


Hope that helps and if not, please feel free to ask another question.

Thanks,

Jay