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What To Do With Lilac Bushes In The Fall – And What Not To!

Did you know that the care you give your lilac bushes in the fall can make a huge difference in not only whether or not they bloom the following year, but also in their overall health and appearance? 

When it comes to caring for your lilac bushes, it’s more about what you shouldn’t do before winter arrives than what you should do. It’s a definite case of less is more. However, with that said, there are still a couple of simple but important tasks that need to be done to help your lilacs prepare for bigger blooms next year.

For the most part, lilacs are very hands-off perennials, which is what makes them a popular choice for homeowners. They can grow easily in multiple different soil types and climates. 

Lilac blooms - lilac bushes in the fall
In order to ensure you have stunning blooms again the following year, a few key things need to happen in the fall – along with a few key chores that shouldn’t be performed.

Pair that with the fact that they produce some of the most fragrant blooms in early spring and summer and it’s no wonder why lilacs have been around for years.

However, many gardeners sometimes run into issues with their lilacs not blooming. And all too often the problem is that you cared for them a little too well in the fall. With that in mind, here’s a look at what you should – and shouldn’t do with your lilacs this fall.  

How To Care For Lilac Bushes In The Fall

The Importance Of Deadheading 

Let’s start with one of the tasks that you should do, and that’s deadheading. This is the process of removing old, spent blooms from the plants. 

Even though the blooms are starting to fade, the plant still tries to send the bloom nutrients and moisture. These are wasted resources that the lilacs can and should be storing to power next year’s blooms. 

Ideally, deadheading should occur right after the lilac blooms start to fade in late spring or early summer. But you can also deadhead them in the fall if you haven’t tackled the task yet. See, “How To Care For Lilacs After They Flower”

Deadheading lilac bushes
Deadheading is best performed right after your lilacs finish blooming. But if the old seed heads still remain in the fall, it’s time to take them off!

Simply use a pair of hand pruners or long-handled loppers to cut right below the faded bloom. If your plants are overgrown and too tall to reach all of the blooms, attempt to remove as many as possible. The more you remove, the more energy the plant can save. Product Link: Fiskars 28″ Steel Blade Garden Bypass Lopper

Proper Watering – What To Do With Lilac Bushes In The Fall

Another key fall chore to help next year’s blooms is watering. Lilac plants require a good amount of water in order to stay healthy and productive. Water is also vital to help the plants store enough energy and moisture for next year’s blooms.

Even during the fall months, plants should receive at least an inch of rainwater or hand watering weekly. Unfortunately, this is a chore that often falls to the wayside once the cooler temperatures of fall arrive. 

If you are not getting typical fall rains, its important to water your lilacs by hand. Failing to do so can have a big impact on both the amount and vibrancy of next year’s blooms.

Adding Mulch – What To Do With Lilac Bushes In The Fall

One of the best ways to protect your lilac plants during the winter months is by adding a nice, thick layer of mulch. Not only will the mulch help to retain the water when it rains or you hand water, but it will also protect the roots of the plant. 

A good four to six-inch layer of mulch works to insulate the plant’s roots during the constant freezing and thawing temperatures that often come with winter. Use an organic, untreated material like hardwood or bark mulch. 

Before adding the mulch, remove any weeds or grass that have started to grow underneath the plant. Any growing weeds steal the nutrients and moisture that the lilacs need. 

By adding mulch, the weeds can’t grow and new weed seeds can’t land and germinate once spring arrives. The mulch can stay in place even after spring arrives since the same benefits of stopping weeds and retaining moisture still apply.

What NOT To Do In The Fall With Lilac Bushes

Now that we’ve covered what you should do in the fall, let’s take a look at what shouldn’t be done. First, you should never prune lilac bushes in the fall. In fact, you shouldn’t prune lilacs in the winter or early spring, either. 

pruning lilac branches
While deadheading is okay in the fall, pruning is not. This will remove all the old wood that next year’s blooms are forming on. The result is no blooms next year.

The reason for this is that lilacs form blooms on old wood and stems. This is growth that occurred during the prior spring, summer, and fall. When you remove the branches or stems during these times, you are also removing next season’s blooms. 

The only safe time to prune lilacs is right after they finish blooming. This allows the plants to produce new growth over summer that can set blooms for next year. 

Fertilizing Mistakes – Lilac Bushes In The Fall

In addition to not pruning your lilacs in the fall, you should also not fertilize your plants during this time. 

Before lilacs go dormant in the winter, they are working to store next year’s blooms. In addition, the roots of the plants are also working to store energy and power for the next growing season. 

Adding fertilizer at this time prompts the lilac plants to start growing new foliage instead of storing energy and slowing down growth. While this might sound ideal, any tender new growth will only die out once the freezing temperatures of winter arrive.

Instead, fertilize lilacs in early spring before the plants have started to turn green. This allows the plants to focus the new energy on powering new blooms as opposed to only pushing out new foliage. 

Here’s to properly taking care of your lilac plants in the fall and not overdoing it so you can enjoy healthy plants and beautiful blooms next year!

Simple Garden Life 

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