Lilac Tree Pruning

posted in: Outdoor Flowers

Lilacs are pretty, fragrant bushes when in bloom. Occasionally they are neglected and can become overgrown, thus inhibiting their full blooming potential. Lilac bushes can be maintenance pruned gently each Spring, or old lilac bushes can be hard pruned to rejuvenate the entire plant, resulting in more plentiful blooms.

When to prune lilacs

Lilacs should be pruned when they reach 6 feet tall, or when the branches are over 2 inches in diameter.

After the lilac bush has reached this mature stage, they should be pruned annually, as soon as the flowers have died. Be careful not to cut back too far, as the flower buds for the following year’s blossoms are already developing. If lilac trees are not pruned regularly, they can grow tall and unwieldy, resulting in a lot of hard wood branches, and lilac flowers only at the very top.

pruning lilac bushes

Pruning old lilac bushes

If you have overgrown lilacs, or recently acquired a property with old, overgrown lilac bushes, you will most likely want to prune them. As lilacs are quite resilient, they will withstand a hard pruning. Keep in mind, however, that cutting them back severely will reduce the number of blossoms you have for a few years. Think of it as tough love, because ridding the lilac bushes of old wood will rejuvenate the entire plant.The best time to do a hard pruning is in the spring, before growth begins.

Cut the entire lilac tree back to several inches above the ground, and you will be rewarded with new growth the following year. It will be several years before you see blooms, though.

If you don’t want to take drastic measures, cut the lilac plants back by a third each year. Keep in mind you still won’t have blooms for another year, but you will have more shrubbery left.

How to prune lilacs for maintenance

Although they are resilient shrubs, you do need to prune your lilacs carefully if you want to enjoy flowers year after year. The key to pruning lilacs is to not cut off their flower buds, which are often difficult to see in the early stages. They are generally directly below the existing blossoms, so if you cut back too far you won’t have flowers the next year.

You will also want to take out the dead branches, suckers, and excess branches from the center of the bush, which will allow for better air circulation. Lilacs are susceptible to powdery mildew if they are in a poorly ventilated area.

pruning lilac trees

The best tools to use are hand pruners or loppers, as you can be more accurate in your cutting. Try to stay away from electric hedge clippers, as you may unintentionally cut back too far. Plus, trimming lilacs by hand gives them a more natural look. If nature intended for them to be box-shaped, they would grow like that on their own.

Results of pruning lilac bushes

By pruning your lilac bushes annually, you will be rewarded with healthier shrubs. You will also be rewarded with a more bountiful blooming period, which can last for two to three weeks if you grow only one variety. If you want to enjoy a longer blooming period, plant lilac varieties that bloom at different times. You could get as long as two months of blooming if you plant several varieties.

When you’re getting ready to plan your garden, or add to it, don’t forget to incorporate some lilacs trees or bushes. There are hundreds of varieties of lilacs available in an array of color shades, but the pruning methods are the same. Keep your lilac bush pruning schedule and you will have beautiful blooms and bushes for years to come.