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.
Where should a lilac bush be planted?
When the lilacs begin to blossom, it is a solid indicator that spring has arrived for good. While many people only have a limited knowledge of common lilac (also known as French lilac) shrubs that can reach a height of 15 feet or more, there are now a lot more options available than there were fifty years ago. Some varieties that rebloom enhance the garden’s appeal the entire growing season.
How to Choose Lilacs
The common lilac is what you will most likely find when you go plant shopping. This traditional plant comes in a variety of cultivars and variations, each of which yields fragrant spring flowers in pink, purple, white, or even combinations of those hues. Common lilacs are typically the most fragrant variety of lilac and can grow to be rangy and large.
Rebloomers have arrived in the garden center thanks to recent introductions of hybrids between the common lilac and other shrub-type lilacs. Some of these more recent types are a little less fragrant, but they also tend to be smaller, bloom more frequently throughout the growing season, and have fewer powdery mildew issues.
The tree lilac is another common variety of lilac. It can grow to a height of around 20 feet and blooms with cream-colored flowers in the middle of the summer. Though it doesn’t require much trimming, keep in mind that the tree lilac is a tree, not a shrub.
Where to Plant Lilacs
Lilacs should be planted in full light (at least 6 to 8 hours per day), as too much shadow will prevent them from blooming. Lilacs also prefer moist, well-drained soil that is slightly alkaline.
When to Plant Lilacs
Before the ground freezes in the late fall is the ideal time to plant lilacs. After the earth thaws in the early spring, that is the next ideal period to plant. Lilacs will likely need to be planted as soon as you can locate them at the garden center, which is great; if you choose to do so during a warmer season, they might require additional watering.
How to Prepare the Soil for Planting Lilacs
A soil test should be performed prior to planting since lilacs thrive in slightly alkaline (6.5 to 7.0 pH), moist, well-drained soil that is high in organic matter. Lime must be added to raise the pH if it is below 5.5. It’s time to get the soil ready when you’ve obtained the ideal pH. Improve individual planting holes by mixing Miracle-Gro Garden Soil for Trees & Shrubs in a 50:50 ratio with the natural soil to give lilacs a nutrient-rich start. Iron and phosphorus are also present in this garden soil to promote root development and ward off leaf fading.
What kind of root structure does a lilac shrub possess?
Ivory Silk, a type of lilac tree, can grow up to 30 feet tall and 25 feet wide. Ivory Silk grows in full sun and is cold hardy in USDA Plant Hardiness Zones 4 through 7a. Even as a young tree, it provides an abundance of summer blossoms. Since the lilac tree is dormant in the fall, that is the perfect time to dig it up. A lilac tree’s deep and extensive root system frequently results in a big rootball that requires the assistance of two or more people to remove from the ground.
At a height of four to five feet off the ground, at breast level, gauge the tree trunk’s diameter. The diameter of a lilac tree at breast level is a good indicator of the rootball’s size, according to a study published in the Journal of Arboriculture.
To determine the rootball’s approximate diameter, multiply the trunk’s diameter by 14.
- Ivory Silk, a type of lilac tree, can grow up to 30 feet tall and 25 feet wide.
- A lilac tree’s deep and extensive root system frequently results in a big rootball that requires the assistance of two or more people to remove from the ground.
Create a trench that is wide enough to fit the rootball all the way around the tree. Use flour, spray paint, or a garden hose to mark the cut line. Put the spade into the dirt as far as it will go while standing outside the circle and facing the tree. Make a V-shaped trench by pushing the shovel in the direction of the tree.
Continue to remove as much of the rootball as you can by digging down and into the lilac tree’s center. To release the roots, clear the earth using a shovel. When the rootball has as much of the root system as feasible, a transplanted lilac tree has a higher chance of surviving.
- Create a trench that is wide enough to fit the rootball all the way around the tree.
- Make a V-shaped trench by pushing the shovel in the direction of the tree.
Move the lilac tree to one side and place a piece of canvas that has been rolled below the rootball. Roots that go beyond the anticipated rootball diameter should be removed with loppers. Unroll the canvas while pushing the tree in the opposite direction. Wrap the trunk and rootball in the canvas.
Remove the rootball from the hole and tie the canvas tightly around the trunk with twine, wire, or a strong cord. Use a wheelbarrow or garden wagon to move the lilac tree to its new site.
By affixing a rag or other marker to a limb facing north, indicate the tree’s north side. This will make it easier for you to move the tree and keep it pointed in the same direction. A lilac tree with a 1 1/2-inch diameter has a rootball that is 22 inches in diameter, whereas one with a 6.3-inch diameter has a rootball that is 83 inches in diameter.
Without tree removal equipment that can dig deeply enough and sustain the weight of the rootball, moving a rootball with a diameter greater than 3 feet is not practical.
How do you prevent the proliferation of lilacs?
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.
How are lilac roots prevented from spreading?
“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.
A lilac shrub can it be kept small?
Keep in mind that there are new dwarf types of lilacs available, such as the repeat blooming “Boomerang,” that tend to stay much shorter in height and can easily be kept shorter than 6 feet tall with yearly pruning.
What kind of area does a lilac shrub require?
Lilacs require a lot of space to grow, so that is the first planting rule. They will want a spot that is at least seven to eight feet broad for a hedge and 10 feet wide for a shrub.
Additionally, they require at least six hours of sun each day in order to bloom beautifully. Create an alkaline, well-drained soil. When planting, add a small amount of lime, and then apply it twice a year to keep the shrubs healthy.
Dig a hole for the plant about as deep as the pot or perhaps a little deeper so you can fill the hole with compost. To prepare the lilac roots for spreading out in their new home, remove it from the pot and score the roots. Backfill the hole after placing it in position. Add a little additional compost to the soil’s top layer for an extra boost of nutrients. Thoroughly water. The majority of lilacs are drought-resistant, so once the bush is established, you can let nature handle the watering.