Lavender plants are low maintenance perennials that look beautiful and exude fragrance, however they do have a tenancy to become leggy if they are not properly cared for.
To stop lavender getting leggy, ensure lavender is planted in low fertility soil and avoid using fertilizer as high fertility soils promote leggy, untidy growth. Prune the lavender, ideally twice per year in the early Spring and late Summer to keep leggy growth in check and slow down woody growth.
Keep reading if you lavender is already leggy or you are looking for tips on how to prevent it becoming leggy and help it stay tidy and produce lots of flowers…
Plant Lavender in the Right Soil to Prevent Leggy Growth
Lavenders grow natively in the Mediterranean region of Europe, where they thrive in full sun, low humidity and sandy or gravelly soil. This soil tends to be low to medium in terms of fertility as sand does not contribute significant nutrients to the soil.
Lavenders have adapted to living in low nutrient environments and actually produce the most blooms, oils and healthiest plants under these conditions.
If lavender is planted in nutrient rich soils with lots of organic matter then this will stimulate the lavender to grow a leggy, untidy appearance with lots of foliage growth and fewer flowers.
The same is true if you add fertilizer to the surrounding soil of lavenders, which is why adding fertilizer to lavenders should be avoided. Over fertile conditions often also lead to lavender turning yellow, which is a sign of an excess of nitrogen in the soil.
To prevent lavenders becoming leggy due to fertile soils, you will need to temporarily remove the lavender and amend the soil with course sand or grit in order to reduce the overall fertility of the soil.
This will help recreate the soil conditions of the Mediterranean where lavenders grow naturally.
Fork the lavender out the ground carefully to avoid damage the roots, avoid using a spade or shovel for this as it is very easy to accidentally slice through roots.
Add course builders sand or grit to a depth or around 18 inches for large lavender varieties and mix it in well so that there is approximately 30% sand or gravel to 70% soil. Too much sand or gravel is always better then too much fertile soil so you can afford to be generous with the sand.
Replant the lavender into the amended area and water in well to avoid transplant shock. For more information, read my guide on the best practices for moving lavenders and avoiding shock.
The sand or gravel will also create the optimal fast draining soil conditions that lavenders need to stay healthy.
Not only will this contribute to the prevention of leggy lavender but it will also increase the blooms, oil and smell of the lavender. Well cared for English lavenders can live for up to 15 years with the right conditions.
Prune Lavender Twice Per Year to Stop Leggy Foliage
In order for lavender to maintain a tidy appearance and display more flowers it will need to be pruned every year after it becomes established.
The first prune of the year should be in the spring just as the new green leaves are emerging at the base of the plant.
Pruning lavender is very simple, all you need to do is remove the top third of the green growth and shape the plant into a nice even round, mound shape.
The mound shape is important as this will help prevent the lavender resist the effects of weather and keep it tidy so it does not become leggy.
What you need to avoid is cutting back into or near to the woody base of the plant as growth does not generally rejuvenate from this part of the plant.
(Reading my article on slowing down woody growth for the base of the lavender).
Cutting the lavender back too harshly is often the cause of leggy lavender so ensure that you trim just the top third of the green growth.
If you do not prune in the spring with the goal of a mound shape the lavender will be more susceptible to splitting, look leggy and untidy.
Pruning the lavender will slow the growth of the woody base and extend the life of the lavender, similar to how regular pollarding extends the life of a tree.
For a visual guide here’s a great YouTube video on how to prune lavender in the spring for a clean, healthy, non leggy appearance.
Prune and Tidy Lavender in the Summer
Pruning lavenders lightly in the summer is good practice as it further prevents leggy growth and prepares the plant for winter.
If you have pruned well in the spring, then only a light prune/harvest will be required at the end of summer. Do not cut back the lavender too hard in the fall as there will not be much time to heal wounds and prepare for winter.
Simply cut back any of the long flower stems that have faded flowers (before the set seed) or you can harvest the flowers through the season for fragrance, potpourri and other decorative purposes in which case the best time to harvest is in the mornings as this is when the oil is most concentrated.
Keep up a good pruning regime every year and you will have healthy, long lived lavender with lots of flowers and avoid a leggy or untidy appearance.
Key Takeaways:
- To avoid lavender becoming leggy it is important to avoid using fertilizer and plant the lavender is low to medium fertility soil.
- Lavender thrives in low to medium fertility soil so you may have to amend the soil with sand or grit which are lower in nutrients and provide the optimal soil structure to prevent lavender from becoming leggy.
- Pruning lavender twice per year will result in neat and tidy lavenders. The first prune should be in the early spring just as green leaves are emerging from the base of the lavender. The second prune should be a lighter trim in the late summer to neaten the appearance and limit any leggy growth. This will also extend the life of the lavender and stimulate more flower growth.