Buzz
The Lilac (Buddleia davidii) is a shrub that grows quickly and produces flowers in abundance. It is a beloved plant among gardeners because of its pleasant fragrance and ability to attract pollinating insects. Due to its rapid growth, you will need to prune it every spring before the new buds start to appear.
Steps
Pruning Lilac Bushes
Prune at the beginning of spring. The timing of pruning plays a crucial role in the care of your lilac bush. You should always prune your plant at the start of spring. March is typically the best time, but the exact timing depends on your region. Late spring frost in some areas can damage the lilac bush.
- The pruning schedule primarily depends on the local weather. As mentioned, if you prune too early, a late frost can harm the plant. However, waiting until late summer or autumn is risky for the bush. If the new shoots are not hardy enough before winter, they could die from the cold, and the plant may not survive the next spring.
- Pay attention to weather forecasts, especially if you live in a colder or unpredictable climate. If a freeze or snowstorm is predicted within the next 10 days, hold off on pruning. Wait until the weather stabilizes and temperatures remain consistently above freezing for a couple of weeks before trimming the bush.
Prune heavily in the spring. Lilacs bloom on new wood. Even if the plant shows no signs of damage or decay, you should trim back all the branches at the start of spring. This will encourage the plant to sprout new shoots and continue blooming throughout the flowering season.
- Lilacs grow in clusters from branches sprouting from the same location. You will prune the plant by cutting back these branches.
- Make sure the branches are left at least 30 cm tall. Stop cutting when the branches are about 30 cm high, as cutting shorter could damage the plant.
- Once pruned, the lilac bush will resemble a set of antlers. Don’t worry about cutting too much. Such heavy pruning is meant to help the plant bloom after the rainy season.
Remove old wood. Lilacs can become overcrowded if the branches grow too vigorously. If the bush seems too dense, it’s best to remove all the older branches rather than just trimming them.
- It’s easy to distinguish between old and new wood. The new branches are green, while the old ones are darker, with peeling brownish-gray bark, and have a more woody appearance.
- Dig up the old branches right at the base to prevent them from regrowing the following season.
Remove spent flowers throughout the blooming season. The main pruning should be done in spring. Lilac flowers bloom in multiple spots across the plant. Both the main branches and the side shoots growing from them can produce flowers. Make sure to look for any spent flowers on all parts of the plant.
Care for the plant after pruning
Apply garden mulch at the start of spring. Spread garden mulch or organic compost around the base of the plant to retain moisture and suppress weeds. A layer about 15 cm thick around the root zone is ideal.
Plant new lilacs 1.5 m – 3 m away from the existing bush to give each plant enough space to grow.
- Lilacs can grow, sprout, and extend their branches outward, so it's important to ensure they have ample space for healthy development.
Water the plant properly. Lilacs need regular watering, with the amount depending on the season. Young lilacs will need more water compared to older plants.
- Although lilacs are drought-tolerant, prolonged dry soil can cause problems, so it's crucial to water regularly during dry months.
- Water thoroughly around the base of the plant, ensuring the soil stays moist but not soaked. Lilacs need more water during the blooming period, so water at least once a week before the flowers bloom. In hot or arid climates, you may need to water twice a week or more.
- Once fully grown, lilacs will require less water, but check the soil often to ensure it remains moist. If the soil feels dry, water until it's lightly moist.
