Last updated on January 24th, 2022
Our site is reader supported, this means we may earn a small commission from Amazon and other affiliates when you buy through links on our site.
Lavender Plant Guide
Lavender, also known as ‘Lavendula’, is a very popular evergreen shrub that produces the most fragrant, beautiful flowers. It can be grown in many planting situations, from a small low-growing formal hedging to potted Lavender on the patio. They will grow in most soil types as long as it is well-drained. They are relatively drought tolerant once fully established.
Lavender is also known for being a herb and is used in many dishes. It has even been known to deter cats as they seem to dislike the smell. Hardy Lavender will live for up to 20 years but more tender varieties tend to last around 5-6 years.
There are many varieties of Lavender but the most common and hardiest is English Lavender (Lavandula angustifolia) and as such makes an excellent variety for forming hedges.
Did you know Lavender contains high levels of nectar and attracts bees helping the threatened bee population!
Picture taken by Christopher Hilton
Lavender dislike waterlogged soil so they are best planted in well-drained, poor or moderately fertile soil in full sun. It grows well in rock and coastal gardens. If your soil is damp or waterlogged, try adding organic matter and coarse grit to the soil to help improve drainage. For informal planting, space plants approximately 45-90cm apart depending on their eventual sizes. They look well planted in groups of 3-6 plants.
Growing Lavender in pots
Growing Lavender in pots is ideal for some of the more tender varieties such Lavandula pedunculata ‘James Compton’ AGM and the Lavandula ‘Regal Splendour’ as they can be placed in a greenhouse over winter or in more sheltered areas of the garden. They are best grown in larger pots, giving them plenty of room to grow in a multi-purpose or loam-based compost (soil-based). As they prefer well-drained soil you need to mix coarse grit into the soil at a rate of 70% compost and 30% grit. This will enable the Lavender to have the best growing condition possible. Don’t feed Lavender too often because they thrive in poor soils. Adding a sprinkle of potash can help encourage flowers and during the winter they are best left fairly dry to protect them from rotting off.
Growing Lavender as a hedge
Lavender makes an excellent low-growing hedge and provides a mass of highly fragrant purple/blue flowers over the summer. The best varieties for forming a lavender hedge are Lavandula ‘angustifolia’ and ‘intermedia’ because of their hardiness to frost and weather tolerance. Lavender needs to be trimmed every year after flowering, cut away a few inches of new growth ensuring you do leave a good amount of green growth as it does not shoot very well from old wood. Plant in rows approximately 30cm (1ft) apart to form a dense compact hedge.
If you are planting a hedge in soil that is clay and not well-drained then try adding some organic matter or mulch and gravel to the soil to help improve drainage. Once the ground is better prepared try forming a mound to plant the lavender in so that the base of the plants are slightly raised. By doing so you reduce the risk of the base of the plants getting too wet.
A Lavender hedge planted in rows – Source: Wikimedia.org
As they thrive in poor soils they need very little feed, however, we do recommend applying potash to the soil in spring as this will encourage more flowers with better colour. Do not feed with high in nitrogen feed as this will promote more growth, meaning it will be long and leggy.
Try drying out the fresh flowers and using them as potpourri in the home for a lovely lavender scent
Lavender needs to be pruned every year to keep a good compact shape. If they are left unpruned then they tend to become woody and do not recover very well. When you are pruning, be careful because they do not reshoot freely from old woody stems. Older plants that have been left unattended are usually best removed and a fresh new plant put in its place. Prune in either spring just before new foliage shoots or in the late summer after flowering has finished. Remove about 1-2 inches of growth, leaving plenty of green foliage for the new growth to shoot from.
Hardy varieties will handle being pruned back hard so don’t be afraid to prune back a good few inches even up to 6 inches if necessary.
More tender varieties tend to flower for most of the summer so it is hard to know exactly when to prune. Prune hard after flowering and then prune again later in the season just to tidy up the plant.
All Lavender will benefit from being dead-headed as the flowers finish throughout the summer, simply remove spent flowers and the flower stem back to the main growth.
The easiest and usually most successful way to propagate Lavender is by taking a cutting. You can either take softwood or semi-hardwood cuttings in the spring from new foliage or take hardwood cuttings in late autumn after flowering has finished.
To take softwood or semi-hardwood cuttings you will first need to take a freshly cut cutting that is approximately 2-4 inches long, remove any leaves and cut the top of the cutting just above a bud and just below the lowest bud. Make sure the cuts are clean cuts, add a rooting hormone to the bottom of the cutting and place them in a suitable pot.
If you use a large pot you can put several cuttings into one pot. The compost should be a mixture of seed compost and sharp sand (50/50). Place them in a greenhouse or cold frame. The cutting should be ready to transplant into small pots in spring.
To take a hardwood cutting complete the same process as explained above, however, take the cutting after flowering in the late autumn.
How to overwinter
Tender varieties need overwintering to protect them from severe frost and wet weather. Tender plants are best grown in pots and you should allow the plants to become dry before watering again. They will handle becoming dry but will not handle being too wet and damp. For tender varieties, we usually recommend pruning in spring. Overwinter them in a greenhouse or in a sheltered position against a wall or fence where they will not get too wet.
Common Problems and Pests with Lavender
Lavender is generally pest and disease free, however, in recent years they have been affected by the Rosemary Beetle, this is easily identifiable by its metallic green with red striped shells. Their larvae and the adults eat the foliage and leave plants looking shabby and although adults can be removed by hand the larvae are not as easy to spot. As most gardeners use Lavender for culinary reasons there are not many pesticides that can be used. One pesticide that has proven effective though and can be used on Lavender plants you are using for cooking dishes is the Provado Ultimate Bug Killer.
Rosemary Beetle on Lavender – Source: wikimedia.org
Rosemary beetles usually affect plants in the late summer and early spring so treat at first signs of damage. Provado contains thiacloprid and is a systemic pesticide which means it goes into the plants’ system and when the beetle or larvae eat the foliage they take in the pesticide and it controls them this way.