Lilac bushes can give any garden a burst of color and fill it with a unique fragrance. No matter what your garden landscape, lilacs can be a great addition.
One thing many gardeners may not be aware of is the importance of pruning to help keep them vibrant and looking their best. Leaving this too long, and lilacs can grow out of hand and become hard to manage.
If this happens, you can lose the appearance and they only flower on the very tips, so pruning helps keep them smaller and retain their form.
In this guide, you can learn when to trim a lilac bush and the best ways how to trim lilac bush to keep your plant healthy and looking its best year after year.
When to Prune Lilac Bushes
In related articles, you will see the mention of many different varieties. Here the more common type (Syringa Vulgaris) can flower without much intervention, and thus, they do need annual pruning, so there is a balance of the new shoots flowering, and some older stems.
Besides this, there can be the times when overgrown lilac needs to be cut back. Doing so helps the bush revive if it has thick stems and shows signs of very few flowers.
Many newer varieties can be fast growers and can require pruning between two and three years. Generally speaking, should the stems reach 2-inches in diameter, then the lilacs require pruning.
One thing you can notice if you stick to a routing pruning plan is that your lilacs can grow to around 8-feet. And they will have flowers all along the branches rather than just the tips.
The right time for pruning lilacs is right after the flowers fade in the early spring. Once you do this, your plants set the buds for new growth for the following year.
Should you prune your lilacs late, it means you can be forfeiting your next year’s flowers.
Also, if you prune early, you allocate more time for the new shoots, and they can dedicate more energy in their development of flowers for next spring.
Lilac Pruning Equipment
- Bypass Pruner
- Step ladders (optional if you have tall bushes)
- Pruning Saws (optional)
Regular Pruning Maintenance
When the time to prune lilacs arrives, as with many other plants, you should not cut more than a third from the stems each year. Because of this restriction, you can ensure new stems develop while the older stems bloom.
One aim for gardening for beginners is to have 8 to 12 stems that offer a range of ages, and they range from 1 to 2 inches in diameter.
Cut Back Unsightly Features: Your first step is to prune away any dead or diseased stems, any twiggy growth and thin suckers around the size of a pencil. It would help if you cut all these back to ground level.
Cut Away Thick Stems: Two inches is the largest you should allow any stem to be. When you remove any more extensive than this, you can stop your lilac bush growing too tall. Just cutting the tops doesn’t work as you can leave your bush a funny shape. If the stems are thick, you may need your pruning saw.
Prune the New Stems: To make your lilacs more like shrubs, prune the new stems back to one of the outward-facing buds. Doing this can lead to more branching, and you have a denser bush as a result.
How to Rejuvenate Old Lilac Bushes
If you have a lilac that is out of control, you can bring it back in line with some radical pruning. If you undertake any rejuvenation pruning, you will see the best results in around three years.
Using the method, you have two approaches. First, you can use the rule of third. Here, you will prune a third of the older branches to the ground every year for 3-years.
You will lose the flowers in the current year, yet you can revert to regular pruning after your 3-years. The aim here is for the new shoots to be the majority of your plant.
A more drastic approach is trim to around 6 or 8 inches above the ground at the start of the growing season in the early spring. Once you do this, let them continue to grow through the growing season and add compost or balanced fertilizer to help promote new growth.
Once you reach the following spring, you can begin pruning lilacs growth that appears spindly while retaining the healthy shoots. Doing so also allows you to control the shape of your plant as it grows. (Read Outdoor Gardening Bench Reviews)
As other pruning, you can control the growth shape by cutting the shoots just before a bud.
Lilac Pruning Tips
Two other varieties of lilac that look the same as the common lilac variety are ‘Palibin’ Meyer lilac (Syringa Meyeri ‘Palibin’) and ‘Miss Kim’ Manchurian lilac.
You will find here that they don’t need as much maintenance pruning, yet you can prune these to retain their shape if necessary. Also, they can benefit from deadheading where you pick any dead blooms from the bush by hand.
However, while convenient, this deadheading is only a benefit for blooming during the first couple of years of growth.
If you have new lilac plants, you will see them bloom from 2 to 5 years, and it is here where deadheading helps as their energies are focused on developing more buds.
Summers that come with extreme weather may yield fewer lilac flowers than a summer that has pleasant weather. You will find this every so often, and it isn’t the way you cut back when pruning lilac bush. (Read Outdoor Ferns Guide)
With any success, you can drop a mail to our email address, or ask more questions.