Lilac bushes are hardy, reliable, and beautiful, so they are a great addition to any yard or garden. However, they require some maintenance, especially because they will continue to grow and become unmanageable if you neglect to prune them. There’s a right and a wrong way to cut back a lilac bush, and it’s essential to know the difference.
You cannot cut a lilac bush to the ground. Instead, cut lilac bushes back to within 6-8 inches (15-20 cm) off the ground in late March or early April for the best results. Cutting it back is a sensible option, but cutting your lilac to the ground will affect its future flowering potential.
Lilacs can become unruly if left to their own devices, and cutting a lilac back can improve the plant’s health and fertility. Maybe you are interested in adding a lilac bush to your yard or already have one and want to know how to care for it better. If so, read on to discover the right way to cut back a lilac bush to encourage new growth.
Things to Consider When Cutting Back Lilac Bushes
A good rule of thumb when pruning lilac plants is to only cut back rangy mature bushes to 6-8 inches (15-20 cm) to ensure productive growth. It’s crucial not to cut Lilac bushes back to the ground because doing so removes the flowering growth, which means it will be years before lilac flowers grow again.
If you cut a lilac bush back too far, you will lose your lilac blooms for one to three years. Lilacs are beautiful flowers, so you don’t want to risk not seeing them for so long.
If you neglect your lilac bushes, they grow uncontrollably and get so large and congested that new blooms struggle to grow. Eventually, large amounts of the bush get so shaded by the upper portions that they lose their leaves and flowers, which results in an unattractive bush.
However, cutting the plant back in late winter can induce more shoots to develop.
Try to wait to cut your lilac bush back until there is no longer a risk of frost, as frost would significantly damage any wounds inflicted on the plant due to you cutting it back. Once you’re sure that frosty conditions are over for the year, you can start tending to the lilac bush.
Pruning Tools and Steps for Lilacs
First, make sure that the bush is ready to be cut back. You won’t need to cut most lilac bushes back until they are 6 to 8 feet (1.8-2.4 m) tall. If your bush is tall enough to be a distraction or doesn’t seem healthy anymore, cutting it back will help revive it.
To cut back a lilac bush, you’ll need the following tools:
- Bypass pruning shears
Once you have these tools, you’re ready to begin.
- Sanitize your cutting tools with a 70% alcohol-based solution to prevent cross-contamination from other plants.
- Use the pruning shears to cut away any dead stems.
- Cut back any stems with a diameter thicker than 2 inches (5 cm). This cutting helps prevent the bush from becoming overgrown and unsightly. Try to cut the stems back to the same length so the plant has a consistent shape.
- Cut just beyond any buds that are facing away from the center.
- Trim everything down to 6 to 8 inches (15-20 cm) from the ground using the loppers or the pruning shears, whichever works best for you. You may even need a pruning saw if you have thick stems.
- Fertilize with a compost fertilizer to encourage growth. All-purpose plant food will do fine.
Another method is to cut back a third of the oldest branches of the bush to the ground each year, rotating which stems you cut. This method will cause you to lose flowers, but the flowers will be back after three years, and your bush will be beautiful again.
However, remember that you should never cut the entire bush to the ground unless you don’t want any flowers for a couple of years.
Benefits of Trimming a Lilac Bush
It may seem counterintuitive to cut a plant you’re trying to keep happy and healthy, but there are many benefits to cutting plants back.
Here are a few:
- It avoids overcrowding because lilacs can reach great heights and become unmanageable and unattractive when left alone.
- You can remove dead or dying leaves or flowers to help the plant become more aesthetically pleasing.
- Getting rid of the dead parts of a plant helps deter pest infestation.
- Cutting encourages healthy flower production.
- Regular maintenance encourages new growth and prevents your lilacs from becoming leggy with uneven foliage and reduced blooming capacity.
As you can see, there are many advantages to pruning your lilacs correctly and regularly, so don’t be afraid to grab your pruning tools! There’s no need to worry about the lilacs not growing back.
Planting New Lilacs
Lilacs are long-lived plants that can last several decades with proper care and maintenance, including pruning. However, years of neglect or poor pruning practices can make them susceptible to diseases and poor health, causing them to wilt and die.
Luckily, you can plant and grow lilacs easily by keeping the following things in mind:
- Lilac bushes need fertile and well-drained soil: It is best to mix compost with the soil to enrich it enough to support a lilac bush.
- Water your plants deeply but infrequently: If lilacs are too wet, they will not bloom, so make sure to plant the bush in an area with good drainage.
- Lilacs love the sun, so they’ll need to be where they get at least six hours of sunlight every day.
- Plant them when the temperatures are cool: You can plant them in the spring or fall, although you should plant the bush in the fall for the best results.
You’ll need a sucker or a nursery-bought lilac bush to plant a bush. A sucker is an offshoot of a root system of a plant. If you have friends or neighbors with lilac bushes, you can ask them if they’d be willing to give you a sucker.
Once you have the sucker, you need to dig a hole, put the sucker in, and cover it with soil. If you water regularly, a lilac bush will grow.
Planting a nursery-bought lilac bush is even easier. Dig a hole and spread out the plant’s roots as you place them in the ground. Then, backfill with soil and water regularly.
If you’re planning on having more than one bush, make sure that there are at least 5 feet (1.52 m) between each one so they have room to grow.
Lilac bushes require regular pruning to encourage new growth and maintain their shape and pleasing appearance. Never cut lilac bushes to the ground. You won’t see lilac flowers for years if you’ve removed the flowering growth. For the best results, cut back a lilac bush to 6 to 8 inches (15-20 cm) off the ground.