With its powerful fragrance, silvery foliage, and purple spikes, lavender instantly evokes Mediterranean landscapes. This hardy plant demands little care, provided it receives sun, well-drained soil, and appropriate pruning. Here’s how to maintain lavender in the ground or in a pot and keep its compact silhouette for a long time.
Lavender or Lavandin: How to Tell Them Apart?
What you take for lavender may actually be lavandin, its close cousin. These two plants belong to the genus Lavandula, but they don’t have exactly the same characteristics.
The true lavender, also called fine lavender or English lavender, generally corresponds to Lavandula angustifolia. It forms a relatively compact clump and yields an essential oil with a fine fragrance. It can also be used in cooking, in very small quantities.
Lavandin, or Lavandula × intermedia, is a natural hybrid. More vigorous, it bears long stems and many highly fragrant flower spikes. The Grosso variety, commonly grown in the Provençal fields, is one of the most widespread lavandins.
The lavender butterfly, or Lavandula stoechas, is recognized by its large bracts that crown its flowers. Very decorative, it prefers acidic to neutral soils. It is generally less resistant to cold and to winter humidity than true lavender.
Lavender has many advantages. Easy to live with, decorative and fragrant, it also attracts bees, bumblebees and several species of butterflies. Its flowers can be dried to scent laundry or to make homemade crafts.
Where to Plant Lavender to Keep It for a Long Time?
Originating from the Mediterranean basin, lavender loves sun above all. Reserve it a spot that receives at least six hours of direct light per day. In shade, it tends to elongate, flowers less, and become more prone to humidity.
It thrives in light, rocky, sandy, or calcareous soil. A poor soil suits it better than a very rich one, which favors foliage over flowers.
Their main enemy remains standing water. In clay soil, plant it on a small mound or mix the soil with draining mineral materials. Avoid large amounts of compost and thick organic mulches that retain moisture at the base.
The right move
If water pools in the planting hole after a rain, raise the lavender—on a rock garden or in a pot. Wet soil in winter can be more deadly than a severe frost.
The hardiness varies by species, variety, and growing conditions. A well-established true lavender on well-drained soil generally tolerates cold better than butterfly lavender. The latter should be protected in regions subject to heavy frosts.
How to Care for Lavender in a Pot?
Potted lavender is ideal for balconies and small patios. Choose a perforated container, wide enough and, if possible, made of terracotta. This material promotes evaporation of moisture.
Place a drainage layer at the bottom, then use a light potting mix. A blend of potting soil, non-clay garden soil, and coarse sand generally works well.
After planting, water to settle the soil around the roots. Thereafter, let the substrate dry between waterings. It is best to observe the soil rather than follow a fixed schedule.
In summer, potted lavender may need water more often than a plant grown in the ground. Water at the base, without saturating the root ball, then empty the saucer. In winter, greatly reduce waterings.
A repot every two to three years helps refresh the substrate. Lavender needs little fertilizer. Too generous an application produces soft stems and less abundant blooming.
When and How to Water Lavender?
During the first weeks after planting, water when the soil dries deep down. This guidance helps the plant develop its roots.
Once well established in the ground, lavender is drought-tolerant. An irrigation is still useful during a prolonged dry spell, especially in the first year. Better to have spaced but sufficient water than a little water poured daily.
Yellowing leaves, blackened stems, or a plant wilting despite moist soil may indicate an excessive water issue. Check drainage before watering again.
When to Harvest Lavender Flowers?
The harvest period depends on the intended use. For dried bouquets or scented sachets, cut the spikes when the first flowers open. Their color and fragrance will then be well preserved.
Proceed preferably in the morning, after the dew has evaporated and in dry weather. Form small bunches, then hang them upside down in a dark, dry, and airy place.
For culinary use, choose only untreated and properly identified lavender. True lavender typically has a more delicate flavor than lavandin, which can become camphorous and bitter. A few flowers are enough to flavor a dessert, an infusion, or a sugar.
The culinary use of flowers should not be confused with ingesting lavender essential oil, which is far more concentrated and subject to special precautions.
How to Prune Lavender Without Damaging It?
Annual pruning helps lavender maintain a dense silhouette. Without intervention, its base gradually becomes bare and woody. The plant becomes less attractive and sometimes more fragile.
Pruning After Bloom
The main pruning should occur at the end of flowering, typically between July and September depending on the region and variety. In areas with cold or humid winters, avoid pruning too late.
With clean pruning shears or secateurs, remove spent flower stalks and slightly shorten the leafy shoots. You can cut about one-third of the green vegetation to restore the plant’s rounded shape.
Never cut all the leaves from a branch. Lavender has difficulty producing new shoots from old bare wood. A too severe cut can leave dead zones, or even kill the plant.
A Gentle Spring Correction
In spring, wait until the risk of major frost has passed. Remove truly dry or broken branches and gently adjust imbalanced parts. However, avoid abruptly hedging the plant.
You can also leave some faded flower spikes until the end of summer. They will continue to provide resources and shelter for certain insects before pruning.
Can You Rejuvenate an Old Lavender?
A very woody, bare, or sagging lavender is difficult to rejuvenate. Do not cut all its branches to the core hoping for a restart.
You can gradually remove some old branches, provided you cut above a zone still bearing leaves. If the plant has lost most of its vegetation, replacing it is often the safest solution. Consider taking cuttings beforehand.
How to Propagate Lavender?
True lavender can be grown from seed, although germination is sometimes slow and irregular. Plants obtained do not always reproduce the exact characteristics of the original variety.
Lavandin is sterile: it does not produce seeds capable of giving new plants. It therefore propagates by cuttings.
Successful Lavender Cuttings
Propagating by cuttings is done in early summer on young shoots or in late summer on stems that have just firmed up.
- Take a healthy, non-flowering shoot 8 to 12 cm long.
- Remove the leaves from the lower half.
- Plant the stem in a small pot filled with a light, well-draining mix.
- Moisten the substrate without waterlogging it.
- Place the pot in good light, but not in direct harsh sun.
A transparent cover can help maintain humidity. It should, however, be aired regularly to limit condensation and the risk of rot.
When new leaves appear and the cutting resists a gentle tug, rooting is on the right track. Keep the young plant sheltered from strong frosts before planting the following spring.
