The ideal season for planting lilac plants is spring or fall. Make the hole deep and wide enough to fit the lilac’s roots, and then plant it with their spread vertically in the ground. Even if you intend to use them as privacy hedges, you should leave at least 5 feet (1.5 m) between each lilac bush you plant to avoid overpopulation.
A location with lots of afternoon sun and well-drained soil is ideal. Lilac bushes need adequate drainage, so wherever possible, planting lilac shrubs in somewhat higher locations is advised. Lilac bushes should be planted, then given plenty of water and a coating of loose mulch. Keep the mulch light enough not to hold too much moisture, yet thick enough to keep out weeds and preserve some moisture.
Are lilacs sun-loving plants?
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.
How much water do lilacs require?
A traditional flower garden, outdoor space, or decorative pot should all contain lilac plants as they are a staple flowering shrub. Zones 3 through 8 are suitable for growing these fragrant shrubs, and they require very little maintenance. Lilacs need at least 6 hours per day of direct sunlight to produce their best flowers. Lilacs benefit from regular watering after initial planting, throughout active growth seasons (spring), and during prolonged dry spells. Lilacs are fairly drought tolerant once they are established.
It is advised to water your lilac plant once every 10 to 14 days from spring till blooming is finished. The ideal irrigation for lilacs is deep, infrequent watering. Make sure the planting space or container has good drainage. These plants don’t appreciate having their feet wet and won’t bloom if they are overwatered. By saturating air pockets with water and reducing soil oxygen levels, excessive water can strangle the lilac tree’s roots. The first indication that the lilac is overwatered is the plant wiggling.
Does lilac prefer shade or the sun?
Full light and well-drained soil are ideal for lilac growth. Lilacs won’t flower well if they are cultivated in partial sunlight or shade. The bushes can live for hundreds of years after they have established themselves in a new location, even if it may take them three to four years to do so. The plant’s growth may be impacted by the soil pH (alkalinity or acidity of the soil). A slightly acidic to alkaline soil is ideal for lilac growth. Because of their frequent high acidity, New England soils may need to be modified for the greatest lilac growth.
Pruning the blooming stem back to a set of leaves each year will stop seed formation and ensure that there will be an abundance of flowers. Good flowering years may be followed by terrible years if this is not done. Winter trimming will get rid of flower buds since they are generated in the summer before they blossom.
Branch out any diseased, damaged, or dead wood. Renewing pruning is necessary for tall, lanky, and poorly flowering plants; for three years, cut around one-third of the oldest stems at ground level each year. This promotes the development of strong new stems from the base. The plant should have fully recovered after three years, with flowers growing back to nose height.
Despite how resilient lilacs are, they nevertheless require plenty of water as they grow. Lilacs prefer soil that is both moist and well-draining.
Powdery mildew fungus (Microsphaera alni), lilac borer (Podosesia syringae), and scale are the most problematic lilac issues in our region (oyster-shell scale, Lepidosaphes ulmi and prunicola scale, Pseudaulacaspis prunicola). The leaves appear to have pale streaks of powdery mildew on them. Even though it is ugly, it is rarely severe in our environment. In stems and larger branches, often one to two feet above ground level, borers leave 1/8-inch holes. A modest infestation may be disregarded, but more than a few borers require professional diagnosis and treatment. While prunicola scale covers bark with a dusty white mass, oyster-shell scale is appropriately named since the pests resemble 1/8-inch oyster shells on the stems. Control adult scale by chopping off branches that are extensively infested; control microscopic baby “crawlers” with a strong hose spray of water (use a hand lens to see scale). Summer oil and dormant oil both work well.
Are lilacs simple to maintain?
I had a variety of roles as a founding worker at Gardener’s Supply over the years. I currently run my own business, which is called Johnnie Brook Creative. A huge vegetable garden, a seasonal greenhouse, a cutting garden, perennial gardens, a rock garden, a shade garden, berry plantings, numerous container plants, and a meadow garden are among the gardens surrounding my Richmond, Vermont, home. The garden is the only place I would rather be. Check out this Garden Gate magazine video interview from January 2021 if you’re interested in learning more.
Among all shrubs, lilacs are among the easiest to maintain. Their requirements are straightforward: lots of sunlight, excellent drainage, nutritious soil, and yearly pruning. The only maintenance you’ll need to perform is yearly trimming to preserve a great shape, so pick your planting location wisely. You’ll be rewarded with bouquets of scented blooms in the spring.
Lilacs can be planted either in the fall before the ground freezes or in the spring after the earth has thawed. Lilacs are frequently supplied bare-root and dormant in the spring. The plants are merely “sleeping,” not dead. When the roots arrive, take off any packing and soak them in lukewarm water for 10 to 15 minutes. Read How to Plant a Bare-Root Tree or Shrub for planting guidelines. Lilacs are also available in containers. Read How to Plant a Tree or Shrub for details on planting procedures.
Do lilacs thrive in containers?
Lilacs grown in small containers require a lot of room for their roots. They thrive when their roots can spread out and grow into larger plants. We advise using a container that is at least 12 inches deep and 24 inches broad, whichever is larger. Greater root protection from harsh heat or cold results with larger containers. Additionally, it guarantees that the roots won’t be frozen or subjected to extreme heat. The lilac requires less frequent watering as the pot size increases. Black containers should be avoided because they can cause the lilac to become overheated.
Which fertilizer is ideal for lilacs?
Lilac plants don’t require a lot of food or fertilizer. A 10-10-10 fertilizer mixture applied yearly in the early spring is what we advise. (The amounts of nitrogen, phosphorus, and potassium, or NPK as they are popularly known, are represented by the digits 10-10-10 in the formula.) Early spring fertilization of lilacs with a high phosphorus solution encourages blossoming.
Coffee grounds and grass clippings are also excellent sources of nitrogen. Use in moderation since an excess of nitrogen in the soil can lead to subpar blooms. The ideal soil conditions for lilacs are slightly alkaline (6.5–7.0 pH), wet, and well-drained. The soil may become more alkaline by adding bone meal to it. Use Miracle-Gro Shake ‘n Feed Flowering Trees & Shrubs Plant Food in the spring if you decide to feed your plant. Last but not least, lilac plants dislike acidic soil. Epsom salts can be used to encourage blossoming while the plant is dormant.
Fungal diseases
This season, the Lilac Pseudocercospora leaf spot, a fungus, was detected in lilac samples examined by the Plant Disease Clinic. The same symptoms have been recorded (yellowing then browning leaves, dieback).
The PDC places a strong emphasis on sanitation because it appears that Pseudocercospora spores can survive on plant detritus for a number of years (leaves, stems, dead flowers, bark).
- To assist lessen the possibility of reinfection the next season, remove fallen leaves.
- Consistent watering and renewal cutting to reduce density will sustain the stressed plant.
Several of the plants in our landscapes, including lilacs, are afflicted by verticillium wilt. Verticillium dahliae and Verticillium albo-atrum are the two fungi that cause it. For a plant with this fungus infection, there is no cure.
- As a result of the fungi clogging the branch’s vascular system and preventing the transfer of water and nutrients, individual branches turn brown and die quickly.
- To increase plant longevity, increase watering and fertilization.
- The disease can spread across all sections of the afflicted plant, thus the best preventive is to buy resistant cultivars and practice proper hygiene.
Insects
The Lilac Borer, sometimes known as the Ash Borer, is a clearwing borer moth that creates tunnels in lilac stems.
- Frass, sap, and sawdust are warning signs (excrement).
- Some plants can withstand this harm.
- Others see branch dieback, and occasionally the entire plant dies.
- They won’t likely catch anyone’s attention.
Jeff Hahn, an extension entomologist, confirmed that no lilac borer samples have entered his lab this year.
Herbicide damage
Broadleaf weed treatments on lawns may volatilize, changing to a gas, and float onto unintended plants if sprayed during periods of extreme heat and humidity.
Herbicide damage signs like cupping and browning would appear in patterns:
- along a hedge’s one side but not the other,
- bushes positioned in or close to lawn areas, at the same level throughout their bases,
- and most critically, away from the area’s predominant winds.
Lilac hedges next to agricultural fields or other sizable herbicide-treated areas may experience damage in this manner.
How can you hasten the growth of lilacs?
Lilac bushes grow fairly quickly, with some types growing more quickly than others. Any way you look at it, lilac bushes are a fast-growing variety of shrub.
By ensuring that your lilac shrub receives adequate sunlight and is placed in healthy soil, you can hasten its growth. It’s important to carefully and moderately water the lilac bush.
In the spring, fertilizer can be applied to the lilac shrub to help it grow. You should be able to observe your lilac shrub growing quickly each year if you heed our advice.
How are lilacs made to bloom?
Lack of sunlight could also be a factor in your lilac plant’s failure to blossom.
You can grow lilacs that don’t have blooms in a location that is either shadowed by other trees or something else. It won’t bloom, but it will live.
For the best blooming, a lilac bush needs at least 6 hours of direct sunlight per day. It can be relocated or the trees that shade it can be cut back.
Be patient because transplanting lilacs may cause a one-year delay in bloom. To ensure that sunlight penetrates the foliage, you may also need to thin the bush.
Is it simple to grow lilacs?
Did you know that the National Gardening Bureau has designated 2022 as the “Year of the Lilac”? They have a sweet, eerie aroma and are among the easiest shrubs for your landscaping to maintain that bloom in the spring. Find out how to plant, nurture, and prune your lilacs.
About Lilacs
Syringa vulgaris, or common lilac, is prized for its tenacity, dependability, and scent. Lilacs are so hardy that they can live for more than 100 years and frequently outlive the houses they were planted near.
This tiny, multi-stemmed deciduous shrub (or tree) has approximately ten canes and blooms at eye level. The height of a common lilac can range from 8 to 12 feet, depending on the cultivar. The fragrant blossoms are wonderful for cutting and enticing to butterflies.
There are lilac types that come in white, cream, and even pink and yellow, though the blooms are typically lilac/purple in hue (ranging from very pale to extremely dark). Flowers can be solitary or double in number.
Lilacs bloom in northern states from mid- to late spring for around two weeks. However, there are lilac varieties for early, mid, and late seasons that, when cultivated together, guarantee a consistent bloom for at least six weeks.
Lilacs do best in soil that is fertile, humus-rich, well-drained, and neutral to alkaline (at a pH near 7.0). Add compost to your soil to improve it if it is in bad condition. (Learn more about adding amendments to the soil and getting it ready for planting.) Lilacs don’t enjoy having their feet wet and won’t blossom if they are kept too moist, so make sure the planting area drains well.
Lilacs should be planted in full sun, which is defined as having at least six hours of sunlight each day, for the finest blooms.
How to Plant Lilacs
- If you’re fortunate, a friend may offer you a sucker, or offshoot, of the plant’s root system. The sucker will first appear pitiful, but all you need to do is dig a hole, fill it with soil, and then insert the sucker. water next, and then wait. You’ll be rewarded with enormous, fragrant blossoms in 4 or 5 years.
- Lilacs purchased from nurseries can also be planted easily. If the plant was cultivated in a container, spread its roots out as you plant it; if it was balled or burlapped, gently remove the covering and any rope before doing so. Set the plant 2 to 3 inches deeper than it was while it was growing in the nursery and cover the roots with topsoil. in water Then add more topsoil to the hole to finish it.
- Depending on the kind, place multiple lilac bushes 5 to 15 feet apart.
- Apply a layer of compost under the plant each spring, followed by a layer of mulch to keep moisture in and weeds under control.
- If the weekly rainfall is less than 1 inch, water during the summer.
- If lilacs receive too much fertilizer, they won’t bloom. In the late winter, they can manage a few 10-10-10, but no more.
- Spread some lime and thoroughly composted manure around the base of your lilac bush once it has finished blooming. Remove suckers while you form the shrub by trimming it.
Pruning Lilacs
- Since lilacs blossom on old wood, it’s important to prune in the spring immediately following their bloom. You risk removing the wood if you prune later in the summer. A word of advice: It’s time to prune if your lilac flower clusters are getting smaller!
- After bloom each year, cut away any dead wood. Remove the oldest canes by pruning (down to the ground). Take out the tiny suckers. Reduce weak branches until a robust shoot remains. Reduce tall canes to eye level.
- Remove one-third of the oldest canes (down to the ground) in year one, half of the remaining old wood in year two, and the remainder in year three if your lilac is very old and in poor condition. Cutting the entire plant back to a height of approximately 6 or 8 inches is another option for elderly lilacs. Although it sounds dramatic, lilacs are remarkably resilient. This option’s drawback is that it takes some time for the hair to grow back. The lilac will grow back bursting with blooms, so there will be less work and more reward.
- It is important to understand that extreme trimming causes bloom loss for one to three years. For these reasons, a smart pruning program gives the bushes yearly attention in an effort to avoid making dramatic and severe cuts.
The Syringa vulgaris kind of lilacs is the most widely grown and fragrant:
- Try the double magneta variety “Charles Joly” for an early bloom.
- Lilacs in the middle of the season include “Monge,” a deep reddish purple, and “Firmament,” a delicate blue.
- Miss Canada, a reddish pink, and Donald Wyman, a solitary purple, are two late-season beauties.
Syringa x hyacinthiflora, an early-flowering lilac cultivar, opens 7 to 19 days before those of the common lilac. Hummingbirds and butterflies are attracted to its fragrant blossoms.
The cutleaf lilac, a fragrant pale lavender, is one of the common lilacs that may flourish as far south as Zone 9. Common lilacs appreciate cold weather. The beautiful shrub Syringa patula ‘Miss Kim’ has light lilac-blue flowers that eventually become white.
There are tiny kinds for gardeners who simply don’t have the space for the conventional larger lilacs, particularly those in urban settings. Even in a container on your balcony or patio, they will grow.
- ‘Baby Kim’ has a lovely rounded shape, only grows 2 to 3 feet high (and 3 feet wide), and has purple flowers that draw butterflies. Hardiness from Zones 3 to 8 extended.
- Compact lilac ‘Little Lady’ (Syringa x) has dark pink buds that open to lilac-pink flowers and grows to be 4 to 5 feet tall and wide at maturity. Zones 2 to 7 are tough.
- Syringa vulgaris cultivars “New Age Lavender” and “New Age White” were developed for mildew resistance and are quite compact, growing from 4 to 5 feet tall and wide. Hummingbirds and butterflies are drawn to their fragrant blossoms. Zone 4 hardy.