Lilacs are such lovely plants that can brighten up your garden space no matter how small or big it is. From spacing the plants to create an aesthetic balance, to maintaining the productivity, pruning lilacs has numerous benefits. When nurtured with love, you can find some lilac plants grow as tall as 30 feet. Whether you like to raise them as majestic trees or lush bushes everything determines the decision of when to prune lilacs.
With little care, this plant gives healthy blooms and continues to spread by itself. Remember that the blooms appear at the topmost level of the plant. So if you wish to harvest these flowers, you should keep a check on the height. The key is to know when to prune lilacs and how.
When should you prune your lilacs?
The form you wish to create and the purpose of pruning determine when to bring out your shears. Basic pruning for removal of the wilted blooms should be done regularly during the flowering season. Pruning the plant outside the growing season might sometimes hinder the healthy growth in the plant. So, if you are confused when to prune lilacs, towards the end of spring when the plant has finished blooming would be the best time. The plant also needs yearly pruning to keep it more manageable.
If you miss the pruning window in spring, avoid attempting to make up for it in summer. The plant might be developing new buds during this time. During fall the buds gradually start maturing and would be ready to burst out in full blooms the next spring. So, pruning during the fall months is often not a good idea. You might not want to lose any new growth or damage the buds.
That was about the annual pruning plan for this plant. But if you have recently planted lilacs in your garden, you should know when to prune lilacs for the first time once they mature. For a young plant, you should not prune anytime before the stem thickens and reaches around 2-inches in diameter. Once this thickness is reached, you can start your annual pruning routine at the close of spring and thus encourage the best blooms year after year.
Tips to prune lilac to keep the plant looking vibrant and full of blooms
You can understand better about how and when to prune lilacs if you know about the basic types of pruning recommended –
1. Maintenance prunes:
This is similar to conventional pruning that you do for any flowering shrub or tree. Identify dead branches, foliage, and twigs in the tree or plant and trim them off. This is an important step for maintaining the thickness of the bush. When the weak branches are not removed, the shrub ends up growing too wide and unmanageable. Another problem is that the nutrients are absorbed in vain to keep the weaker branches alive. Removing them pushes the nutrients fully to the healthy foliage and encourages better blooms. Religiously following your maintenance pruning would increase the lifespan of your lilac tree.
2. Early pruning
This is for those gardeners who have newly planted their lilac bushes. As the name indicates this is when you trim and maintain the shape of the plant in its formative years. The first 10 years after planting the bush are critical in creating the perfect form. If you spot suckers eliminate them so that the plant starts branching healthily. You might notice suckers growing close to the original shoot. You always have the option of replanting them elsewhere if you have space. This type of pruning lets you prevent the problem of overgrown lilacs with poor looking blooms.
This is one of the most common types of pruning that most gardeners know about. From the main stem, you would notice two young shoots corresponding to the bunch of flowers.
Once the flowers have wilted completely, shear at the base of the bunch close to this branching junction. So, the old flower is removed from the plant and the growth of fresh shoots takes place without the plant having to focus on the flowers further. This step is critical in preventing the formation of seeds. It is as important as tackling the thickness of the bush. It helps in conserving the plant’s energy and nutrients so that new growth can be encouraged. This type of pruning helps with the formation of better blooms the next year. For the removal of dried flowers, the use of clean shears is important. This delivers clean cuts without damaging the shoot.
4. Rejuvenation of the plant
Pruning done to giving a complete makeover to an oddly maintained lilac is called rejuvenation pruning. If you move to a new place and find an overgrown lilac bush, then you can prune to give it a new life. Make sure that you simultaneously balance the process with steps to promote fresh growth. For this, you should choose healthy and organic plant nutrients. Fertilization of the plant along with the addition of natural compost can provide significant improvement. Rejuvenation pruning is not required every year. Only if you find your lilac to be growing out of shape you would have to do it. It can also be done once in three years or as required based on the growth of the lilac and the age of the plant as well.
While pruning your lilacs make sure that you closely inspect the existing branch structures so that you can plan the right places to make the cuts. Grafted lilacs should be treated extra carefully. The joint where the graft was placed would be indicated by a swelling in the spot where there was new growth. If you cut a branch that was grafted you should make the cut above this joint. This would provide a stable growth post pruning. After learning how and when to prune lilacs even the beginners in gardening would be able to maintain healthy-looking plants for years to come.