Brown leaves

[scootless]

I have 3 yr old, old fashioned lilacs, I have only had 2 blooms, 1 has died and the others are growing tall and thin. They have some brown dry spots. Do I prune these or cut them back? Is the brown what happens to them in the winter. Should I cut them back and start from scatch. This spring they seems somewhat happy and I was really hoping that the following spring I would realy start and see some blooms. But now that I am seeing all these brown, dry leaves, I fear they are diseased.

All the advise I find is for mildew. I think what I really need is pruning advice. Help, my grandmother gave these to me.

Cindy

[Newt]

Hi Scootless,

There are several different reasons why your lilac is behaving the way it is. Lilacs have some needs that you may not be fulfilling. Since you aren't registered, I have no way of knowing if you will come back to read this information, so I will be brief and let you do the reading. Take a look at these sites for help. If you don't find the help you need, please register and then post again on this topic at this post and I will get notification of your reply. When you register please be sure and list your state and hardiness zone. If you aren't sure of your zone, the last link will help you find it.

How to Care for Lilacs by HelpfulGardener.com

Newt

[The Helpful Gardener]

That brown in the leaves; does it start at the tip and go black after? Could be Psuedomonas syringiae, or bacterial lilac blight. A quick search of the web brought up a lot of info on how the bacteria is being used to keep fruits from rotting after harvest, so it seems likely to me that the bloom of cases we've been seeing here in Connecticut are an extenuation of orchard practice ( the first case ever seen in the home landscape here in Connecticut was only a few years back and now it is becoming common). So your fruit isn't moldy now, but your lilacs look horrible. It wouldn't kill the plant outright, but it weakens it, allowing other pathogens to attack, or makes it look so crappy you want to tear it out...

First assess the cultural conditions these plants are subjected to, and if nothing pops up there, try the milk trick I talk about all the time. It's sort of the same thing the orchard guys are doing to their fruit with the P.s.; innoculating with one bacteria to eliminate others. One cup milk in a gallon of water (spoiled milk is best) and spray on your lilacs. The bacteria that sours milk (Lactobacillus spp.) is very aggressive and takes out a lot of bad guys (WITHOUT HARMING YOUR OTHER PLANTS!)


Scott