Lavender is regarded as a semi-shrub or subshrub—a plant that looks like a perennial because most of its growth is soft and green but with older base stems that turn woody. So-called "woody lavender" refers to the a plant with older, mature stems.
A hardy plant for dry spots and one of the longest-blooming semi-shrubs around, lavender (Lavandula) would earn a place in most sunny gardens even if it didn’t have such a heavenly scent. There’s more good news: Lavender is easy to prune, and when you do it you’ll be covered for the rest of the day in those aromatic oils. When it's time to prune your lavender, tailor the process to the age and variety of the plant.
When to Prune Lavender
An easy, effective lavender pruning schedule is to prune in the springtime and again after flowering. A slightly more detailed schedule involves three rounds of pruning: pinching off fresh young tips as they are just developing; cutting back stems by about one-third their length after flowering is complete; and removing complete stems late in the season if they have grown old and woody.
Of the three, the most important time to prune lavender is after flowering is complete, but this plant is forgiving. All lavenders bloom on the stems that grew in the current year. This means pruning can be done in early or mid-spring without sacrificing the current year’s flowers.
Pruning in spring can delay flowering—which might be your preference—and it's a good time to take down dead portions and shorten the growth to the buds. Pruning in late summer or early fall before the first frost encourages good air circulation, which guards against rot. So if you have the time, pruning twice a year can be helpful for your plant.
There's little reason to deadhead the individual small flowers on a lavender plant—cutting back entire stems is a more effective practice.
Before Getting Started
Deep at the center of the mounded semi-shrub, your lavender plant is trying to turn to wood. One goal of pruning lavender is to slow down that transformation for several reasons:
- Lavender wood is very weak and prone to splitting due to snow, ice, and rot.
- Lavender is shallow-rooted, which means roots are more susceptible to rot and early death due to too much moisture.
- Regular pruning encourages root growth, especially during the winter months when the plant is storing energy in the roots. A strong root system is essential for a lavender plant to thrive for many years. This is a very durable plant, and hard pruning is unlikely to injure the plant permanently; it always grows back.
- Unlike many true shrubs and trees, the wood that forms on lavender usually does not rejuvenate. Old wood will stop producing new shoots or will produce spaced-out shoots, detracting from the plant's overall appearance.
Watch Now: How to Prune Lavender Plants
Equipment / Tools
- Bypass pruners
- Pruning shears
- Lavender plants
Prune Young Lavender Plants
Start pruning lavender plants while they're still young. Begin by pinching off tips of new growth so that a young plant can respond with dense branching that helps form a good shape and a lot of blooming growth to work with as it matures. Waiting to prune will cause the plant to form woody growth that can't be shaped as nicely.
Pruning Established Lavender Plants
Heavily prune established lavender, cutting back all stems by at least a third after the plant is finished flowering for the season (the exact time for this can vary depending on the lavender variety and your local climate). Lavender in full sun can be expected to grow vigorously each year, so take this opportunity to reform your plants into the green mounds that are lavender’s signature shape.
Pruning Lavender That Is Woody
Continue to heavily prune old plants, but don’t cut down to leafless wood. You can’t rejuvenate plants by cutting into old wood, but you can try to rejuvenate them by pruning to points just above the wood. A good rule of thumb is to count to the third node (a raised bump from which leaves grow) above the woody part and then cut just above it. If you are lucky, all three nodes, as well as some hidden nodes buried in the wood, will wake up and grow for you.
Guidelines for Specific Varieties
Identifying your lavender variety and tailoring pruning to that type will help you get more return for your efforts. There are three common types of lavender:
Lavandula angustifolia: English lavender comes in many varieties, including 'Hidcote' and 'Munstead'. This lavender has single, leafless stems and compact spikes of blossoms. It is generally low-growing and has a compact, mounded shape. English lavender blooms in late spring to early summer. If it's pruned lightly just after its first flowering, it will likely flower again in late summer. After this second flowering, a full pruning—typically in late August—will prepare it for winter and encourage more blooms in spring.
Lavandin x intermedia: This hybrid of English and spike lavenders also has many varieties. The most common are 'Grosso', 'Provence', and 'Giant Hidcote'. Its stems are branched and longer than those of English lavender. The flower spikes also are longer, and they have a graceful taper. Lavandins are mounded in shape and usually larger than English lavender with long stems that tend to fan out from the center. Lavandins bloom in mid to late summer and a full pruning after the long blooming season will prepare a plant for winter. Because of the long stems, you might need to prune as much as half the plant’s size.
Lavandula stoechas: Sometimes called Spanish or French lavender, this is the least hardy of the lavenders with blooms earliest in spring. Spanish lavender has a short, full flower spike with open petals at the top, distinguishing it from other types. Because of its fragility, lightly prune this lavender—never too close to the base—just after the first flowering. Then, follow up with gentle deadheading (removing spent flowers) and shaping for the rest of the season. A slightly more vigorous pruning can be done in late August to prepare the plant for winter and encourage a fuller plant in spring.
Tips for Pruning Lavender
Pruning is generally necessary for the health of a lavender plant. Not pruning lets a plant get large and woody, and it forms nooks that trap water. This can introduce several hazards:
- In summer, trapped water promotes rot in lavender's weak stems and wood.
- In late autumn, trapped water promotes an early frost, ending the growing season prematurely.
- In winter, trapped water can freeze, easily splitting woody parts. Plus, a dense plant or one with sprawling wood is especially vulnerable to snow loads, which can deform or break plants.
So keep an eye on your lavender plant throughout the seasons, and remove parts that might cause problems.