Pruning lavender can seem confusing, with so much conflicting advice available. Thankfully, gardening experts have shared their wisdom on when and how to prune lavender for the best possible results.
Morris Hankinson, managing director of Hope Grove Nurseries, explains why lavender plants need regular pruning. He emphasizes that unless you plan to replace your lavender plants every few years, pruning is essential for their long-term health and vitality. Unpruned lavender plants can become unruly, with leggy growth and sparse flowering. These neglected plants are difficult to rejuvenate and often don’t respond well to hard pruning.
Gardening experts at Sky Nursery agree, emphasizing that pruning is the only regular care most lavenders need to prevent leggy growth.
Lavender experts Nick and Lyndsay Butler, owners of Lavender Fields farm, advocate for annual pruning. They recommend pruning in late August or early September, right after the plant has finished flowering. This timing allows the plant sufficient time to heal before the arrival of frosts and winter.
However, you can prune any time after a flower spike has fully bloomed. Cut the spike at the base where it joins the plant’s stem. This practice promotes vigorous growth and keeps your plants healthy. Additional pruning in early spring can be beneficial for plants that have grown abundantly the previous summer.
When it comes to pruning different lavender varieties, Spanish lavender can be pruned back to half its size for reshaping. English and French lavender varieties can be pruned even more drastically, to a third of their blooming size. Be aware that spring pruning may delay flowering.
Lavender doesn’t readily shoot from old wood, so never prune old, brown, leafless stems. This could kill the plant. It’s best to replace old, neglected plants. Regular annual pruning can help prevent this situation.
Now that you know why and when to prune lavender, you need to understand what to prune. Look for deadhead flowers, wilted or discolored flower heads, and any dead or decaying material. When pruning for the first time, remove spindly or crossing branches to shape the plant and prevent interference with its growth.
Remember, the harder a plant is pruned, the more aggressively it will grow, and vice versa. Be mindful of this when trimming your plants, as it will impact their future growth.
Nick and Lyndsay provide specific instructions for pruning established lavender plants. Use secateurs to remove flower stalks and about 2.5 cm (one inch) of the year’s growth, which is the grey-leafed stem. Aim to prune just above the woody part of the plant.
For French lavender, prune hard to approximately 23 cm (nine inches) after the first flowering and then deadhead throughout the season.
For those who want to maximize flower production, experts recommend being ruthless with pruning. Cut the shoots back by a third, or to around 22 cm (nine inches), into the foliage. This encourages abundant blooms.
Even young lavender plants need pruning. Instead of cutting them, pinch the tips to slow the growth of wood at the plant’s center.
Garden retailer Thompson and Morgan emphasizes the importance of cutting just above a group of new shoots when pruning. Cutting lower can kill the lavender.
After pruning, you can use the cuttings to propagate your own lavender. This is a great way to replace any lavender hedging or plants that may have struggled or needed to be removed. By following these expert tips, you can ensure that your lavender plants thrive and produce masses of beautiful blooms for years to come.
