“Despite weed-blocking fabric and rock mulch, our lilac plants have begun to emerge from the roots. What can we do to eliminate these undesirable sprouts while protecting the main plant? -Elizabeth
What are lilacs renowned for is “sucker growth, or the process by which a plant shoots from its roots. Some kinds are more likely than others to develop sucker growth. They are unfortunately difficult to manage since they produce more as a stress response the more the roots are damaged by digging or cutting the suckers.
Here are some things to try since your landscape fabric didn’t work:
- You might want to choose a plastic barrier cloth that is thicker. The primary mechanisms through which weed control fabric inhibits seed germination and sunlight are nevertheless vulnerable to penetration by shoots and roots. A plastic barrier should stop all development, but in addition to doing so, it also obstructs water and nutrients and traps heat. Any plants enclosed by such a barrier must be watched carefully to ensure that they are not cooked.
- A commercial product called Monterey Sucker Stopper, which contains the growth inhibitor NAA (napthaleneacetate), is intended to suppress the development of suckers from roots and pruning incisions. Although it is offered in a ready-to-use spray bottle for personal gardening, it is frequently utilized in the orchard sector.
- Instead of cutting, remove suckers by tearing. Tearing them off can assist get rid of the dormant buds at the base so you can get the sucker all the way back to the root where it came from.
- Use a sharp spade to dig them up while also getting rid of the root. If you want, you can transplant these.
- Use a sharp shovel to deeply cut the roots in a circle, and then treat the suckers outside the circle with a herbicide like Roundup. Do not apply herbicide to any suckers that are still attached to the parent plant.
- To try to contain the roots, you might also consider enclosing the plant with a 612-deep subterranean barrier, like buried metal or plastic landscaping edging. It can be helpful, but if your lilac is established, its roots probably run deeper than this.
- Make the circle at least 2-3 feet wide, ideally as wide as the shrub’s drip line, using root pruning or underground obstacles.
Naturally, as the plant continues to sprout, the majority of these suggestions will need to be repeated. It’s a difficult battle, but I still have suckers growing from a lilac I dug out and removed ten years ago. Some gardeners choose to ignore the issue and simply allow the shrub to spread, while others choose to fully remove the shrub and have the roots ground out.
How can a lilac bush be kept from sprouting new leaves?
Even the removal of the majority of the root ball and the trunk may not stop a lilac bush from sprouting new growth. In the following growth season, the remaining root tissue could develop suckers. Use plastic barrier fabric or thick organic mulch to block out unwanted growth around lilac trees or old stumps. Apply broad-spectrum herbicides or growth inhibitors, as necessary, to restrict the growth of sucker plants.
How do you manage a lilac plant?
One of the joys of spring is the luscious aroma of lilacs. The lilac bush, which blooms in late April or early May with clusters of tiny purple flowers resembling bunches of grapes, is a common sight in most communities.
These are primarily common lilac shrubs (Syringa vulgaris). Kris Bachtell, vice president of collections at the Morton Arboretum in Lisle, described it as “grandma’s lilac.” It is widely known.
He said that there are hundreds of cultivated types. Although there are cultivars with magenta, pink, and white blooms as well, the majority bloom in hues of purple. They are all resilient and enduring.
Despite being widely cultivated, common lilac is difficult for some gardeners to grow. Even if some newer types are more resistant to powdery mildew, older ones are frequently deformed by it in the late summer.
The plants, which are native to rocky Balkan hillside soil, require full light and well-drained soil. An older lilac’s blooming cycle may end if nearby trees have grown to shade it.
Lilacs require frequent renewal trimming to reduce their size and thin them out. According to Bachtell, this necessitates the yearly removal of certain elder stems as well as dead wood. Lilacs also frequently sprout suckers from their root systems, which may need to be cut back.
The common lilac can simply be too much of a shrub for smaller yards because it is a large shrub or small tree that grows 8 to 20 feet tall and almost as wide.
Fortunately, Bachtell says, there are alternatives. “He said that several other lilac species are somewhat smaller. “They might be more disease- and shade-tolerant than grandma’s.
Meyer lilacs (Syringa meyeri) can reach heights and widths of 6 to 8 feet. Even though it thrives in direct sunlight, it can tolerate some shade. The flower clusters are smaller but very fragrant, and they emerge a little later than those of the common lilac. Autumn causes the leaves to become yellow. Although there are various cultivars, Palibin is the most popular.
One cultivar, Miss Kim, of the Manchurian lilac (Syringa patula), is primarily recognized. On a plant that is 5 to 8 feet tall, it bears delightfully scented light purple blossoms that turn light pink as they age. In the fall, the ruffled leaves become purple-red. Compared to other garden lilacs, the plant is a little more resistant to powdery mildew.
Hybrid lilacs that rebloom in the late summer or early fall do so less profusely than they do in the spring. Bloomerang Purple (Syringa ‘Penda’), Bloomerang Dark Purple (Syringa x ‘SMSJBP7’), and Bloomerang Dwarf Pink (Syringa x ‘SMNJRPI’) are just a few cultivars in the Bloomerang line. They are all smaller than typical lilacs, although cultivar differences in size should be noted on the label.
According to Bachtell, pruning should be done in the first week or two after the spring shrub has stopped flowering if it’s necessary to keep a lilac untangled and at the right size. Pruning in the winter will destroy buds that might otherwise develop fragrant blooms since lilacs bloom from buds that were formed the previous year.
Llamas send out runners, do they?
What a soggy week it has been. However, things may be worse, so we should take a moment to be grateful for what we do have. Look around and discover what lessons nature may teach us while we’re doing that.
Q. Seven years ago, I planted three lilac bushes. The reason I have a problem is because they send out these shoots from very close (about 5 or 6 feet away), ruining my landscaping. How do I put a stop to these runners? They lift up my mulch and tarp despite my clipping and pulling. I work to maintain them tall and unbranched. Newburgh’s Frances P.
A. To expand their total size, French lilacs send out their runners. Installing barriers that extend at least 6 inches into the ground should stop lilacs from encroaching on your garden beds. A polymer-based barrier with steel or metal edging is an option. There are numerous products available. You can spray “sucker stopper” on the already-existing runners, or you can just keep cutting and pulling up the existing runners until they are gone. After you install the barrier and finish eliminating the last of the suckers, you should be free of runners for some time. One variety of lilac—the Miss Canada lilac—doesn’t produce as many runners as others (Syringa x prestoniae).
A. We recently planted a hydrangea with crimson blooms. It appeared to be flourishing, but now we can see that the new leaves, which are largely on the top of the plant, are yellowish. Can you assist us in determining the issue? A Ballos
Iron chlorosis can affect big-leaf hydrangeas (Hydrangea macrophylla). Iron chlorosis is more likely to occur in plants growing in high pH soil because iron becomes less accessible as pH rises. Iron chlorosis is a condition that appears on new leaves, as opposed to nitrogen shortage, which manifests as yellowing of old leaves.
The soil can be amended with iron to treat iron chlorosis. Utilizing a chelated iron supplement is the most effective way to do this. One of these items ought to be available in a garden center, the garden area of a hardware shop, or a mass merchant. Observe the instructions on the packaging closely. In a few weeks, you should start to see progress.
You will probably need to reapply the chelated iron product annually or whenever symptoms return as long as the soil pH stays high. Iron chlorosis can be permanently treated by adding aluminum sulfate to the soil to lower the pH or by mulching the soil with acidic organic materials like pine bark. The issue may be that your hydrangea’s red flower will turn blue as the pH of the soil changes. You’ll eventually get a good balance.
Q. The horseradish root that I grew last year is starting to come out of dormancy. Unfortunately, I lost the planting’s care, feeding, and harvesting instructions. Could you please help? Thanks a lot. Swan Lake, Dennis H.
A. Growing and caring for horseradish is not particularly difficult. In fact, some advise ignoring it altogether until harvest. Although it is a tough plant, I’m not sure if I would completely overlook the horseradish. You seem to have a well-established plant. There isn’t a lot of attention required. Horseradish does not require a lot of fertilizer, so keep it moist during the hot summer months.
You can either harvest your horseradish in the early spring or the fall after the first frost. When you’re ready to harvest it, dig as deeply as you can around the horseradish plant before using your shovel to gently take the horseradish root out of the earth. Replant some of the baby roots that have been broken off in the earth. Ground horseradish can be made using the remaining horseradish root.
Raising horseradish is relatively simple to undertake and may be a delightful and satisfying endeavor if you like it.
Make careful to leave the leaves on your floral bulbs after they’ve finished blooming until they turn yellow (6-8 weeks). If the leaves don’t remain in place long enough to create food to make up for the strength lost during flowering, flower production the following year will decrease. This time of year, bulb-tone or bone meal can also be used to feed the bulbs.
Are lilacs’ roots invasive?
Lilac roots aren’t thought to be invasive, so planting lilacs close to a building’s foundation poses no risk as long as you give them adequate room. The average root spread for lilac shrubs is 1.5 times that of the shrub’s width. In most cases, keeping objects away from the foundation at least 12 feet (4 meters) will prevent foundation damage.
Is it acceptable to prune a lilac bush?
All lilacs should generally be clipped right away in the spring after they have finished blooming. Lilacs set their flower buds for the following year immediately after the current year’s flowers have faded, therefore trimming later in the summer or fall will result in the removal of most or all of the blossoms for the following year. The larger common lilacs as well as the shorter or more “shrub like” cultivars are all subject to this timing guideline. While the “when” of lilac trimming is rather simple, the “how” is a little more difficult. For the time being, we’ll refer to lilac pruning as either maintenance pruning or rejuvenation pruning to keep things simple.
Can you trim back lilacs to the ground?
The lilac tree will resemble nothing more than a twig in the garden by the end of September. It shouldn’t be reduced to the ground, though. Despite the fact that lilac trees are known for their resilience, it will likely take several years before you see blossoms again because you cut off all the blossoming growth.
If your lilac tree is more mature and unruly, it may require more aggressive pruning and some chopping back; just make sure that it doesn’t take up more than a third of the tree.
Can you manage a lilac bush’s height?
It’s critical to understand the type of lilac you are working with. Despite being technically a lilac, it has numerous stems and branches, making it a bush or shrub. There are also larger lilacs that can be cut down to a central stem and meet the height requirements for trees. Lilac blossoms bloom amid the highest branches of tree lilacs, which can reach heights of 25 feet. Smaller and more compact, lilac bushes and shrubs are frequently bred for a high density of branches and consequently flowers.
Many attractive lilac variants are available in shrub and tree forms. Even the common lilac comes in a variety of hues, from violet to pink-mauve to white, and has spread throughout most of Europe and the United States. There are dwarf lilacs designed to fit small spaces, as well as hybrids specifically selected to produce more flowers per unit volume, in addition to the conventional bushes or trees most frequently found in yards.
How long does a lilac bush live?
Lilacs are renowned for their longevity and hardiness.
Numerous lilac shrubs reach ages of greater than 100. They frequently outlive the residence of the gardener who planted them due to their extended lifespan. As a result, if you’re driving along a country road and come across a few what appear to be random lilac bushes, it was probably a farm or house a century ago.
Try growing lilacs in your garden if you haven’t already. They not only return every year, but they also put on a display for the senses with vibrant blossoms and enticing scents. Lilacs have a lot to offer, and learning about their history demonstrates just how unique these plants are.
Can I prune my lilac shrub all the way back?
Older lilacs only bloom on the tallest branches and can have stems as thick as small trees. Fortunately, rejuvenation pruning can bring back a lilac that has been dead for around three years. There are two options available to you.
Using the “third” method is a less harsh way to pull an out-of-control lilac back into shape. For three years in a row, completely remove a third of the oldest branches from the tree. The thickest stems should be removed first. Pruning overgrown lilacs is simplest in the early spring before the branches start to leaf out, even if you’ll lose some blossoms for the current season. Your overgrown lilac should consist primarily of new shoots after three years of consistent pruning. After the plant starts to bloom all over, you may start doing routine maintenance pruning.
You can take the dramatic action of pruning back the entire plant to 6 to 8 inches above the ground in the early spring if you don’t like the way your old lilac looks or you just want a quicker solution. To encourage new development, fertilize the plant with compost or a balanced fertilizer. Throughout the growing season, new shoots will appear; allow them to continue to develop over the summer. The following spring, start cutting the spindly growth while keeping the healthiest shoots and keeping an eye on the plant’s shape. By pruning the remaining shoots to just above a bud, you can promote branching. After this, continue with routine maintenance pruning.