Lilac bushes can be true things of beauty, covered in purple flowers and lush greenery. Unfortunately, sometimes they hit a rough patch and their blooms start to fade while their greenery fades away. If your lilac bush appears to be ailing, follow these steps to attempt to revive it.
Step 1: Trim away any dead branches.
Be very careful when pruning an ailing lilac bush. You do not want to accidentally cut away any new growth, as doing so could stunt the tree's growth even further. Use sharp shears so that you don't cause the branches to crack or split.
Trim away any branches on which there are few to no leaves. If you see any signs of fungal growth on a branch, trim it away, too. Cut the branches as close to their bases as possible. The more dead growth that is left on the tree, the more resources the tree will waste trying to send water and nutrients into those tissues unnecessarily.
Step 2: Spray with a fungicide, if needed.
If you noticed any fuzzy fungal growth on the branches or leaves of your lilac bush, purchase a basic fungicide at your local garden store. Anything with copper as the active ingredient should work well. Follow the instructions on the package to coat the tree evenly with the spray. Some types of fungicides will need to be re-applied after several weeks, so read your label carefully to see if this is the case. Try to apply the fungicide when you're not expecting rain for a few days so it has a chance to work before being rinsed away.
Step 3: Fertilize the tree.
Purchase a generic 10-10-10 or 12-12-12 fertilizer from your garden store. All that this means is that the fertilizer contains equal parts of nitrogen, phosphorus and potassium. Dilute the mixture according to package instructions. Then, starting about 1 foot from the base of the trunk of your lilac tree, pour the fertilizer in a broad circle. This ensures it actually works its way into the soil through which the roots grow. Many tree owners make the mistake of fertilizing too close to the base of the tree, and the nutrients never reach the roots.
Watch your lilac bush over the next few weeks. With any luck, it should begin sending up some new, healthy branches. It may take it a year or two to get back to its full vibrancy. Continue trimming it early each spring and fertilizing it every few months to ensure it does not die back again.
For other information about tree trimming, check out companies like Ironwood Earthcare.