Lilacs are stars of late spring

5/21/2013

Can you smell them? Their fragrance can carry you away this time of the year. Lilacs are really showing off their late spring blooms and will knock your socks off with their bouquet.

Syringa vulgaris are the most common shrubs in our landscapes.

It seems to be a common hand-me-down from generation to generation. If you see one in your neighbor's yard, it can be a good primer for a lesson in their family genealogy and the plants bloom in the northern states for two weeks in late May.

My neighbor says the lilac shrubs in his yard come from his great-great-grandfather and the original plant was flourishing in Siberia. I guess they should be pretty hardy here.

The perfect spot

Luckily, these sturdy plants aren't very picky regarding their soil. But they are a bit selective when it comes to sunlight. I have seen lilac bushes almost 10 feet tall, full of leaves but struggling to push out a few blooms off the top. The shrub is shaded by woods and stretches to find as much light as it can to blossom.

Lilacs are one of the early bloomers and many of them can continue to bloom into late June or even early July in our region. They do well with at least six hours of sunlight each day. They can reach up to 15 feet and are a magnet for butterflies.

Boost the blooms

Since we covet the fragrant blossoms on this shrub, you need to keep this shrub fed. Fertilizer that has a high third number will promote strong blooming in your plant, so feed them in late winter just as they are gearing up to bloom. You can also top dress it with composted manure. Too much fertilizer will stop them from blooming.

When to prune

If you see their flowers getting thin, it is time for a trim. When your flowers look spindly, you can start pruning.

There's a general rule when you are ready to prune your shrubs. Wait until they are done blooming, then get in there and thin them out. Too many times, gardeners will get excited in the spring to cut things back. If you start chopping away at the lilac, magnolia, or forsythia, you will be cutting off all of their flowers.

Lilacs bloom on old wood and will do well next season if you cut them after they bloom. If your shrub has never been pruned, it will take you a few seasons to get it into shape.

The first step is to take one-third of the thickest canes all the way down to the ground. Leave some of the smaller ones to keep the plant healthy.

Cut the others back in the next two years until you have rejuvenated the entire shrub. They will also survive if you cut the entire shrub down to about six inches above the ground. This is a drastic move, but it will survive. It will take two or three years to flourish again, but it will come back.

Contact Kelly Heidbreder at getgrowing@gmail.com.