Overwintering lavender

Overwintering lavender

1. 01

   Which lavender is hardy?

   English lavender (Lavandula angustifolia) and its hybrids are the hardiest lavenders and can usually stay outside all winter in free-draining soil. In a pot, Botanicaly’s plant data puts its limit at about minus 5 °C (23 °F), because roots in a pot freeze faster than roots in the ground.

   French and other tender lavenders are less hardy. Keep them frost free over winter, for example in a greenhouse.

2. 02

   Overwintering lavender in pots

   Roots in a pot are less insulated than in the ground. Frost reaches the pot from all sides, and roots take cold worse than shoots.

   Move the pot to a sheltered spot, such as the foot of a wall, out of harsh weather and heavy winter rain. Wrap it in several layers of bubble wrap or a coir mat, or stand it in a bigger container filled with leaves or straw. Keep the drainage hole clear.

   In very cold areas, or if the variety may not be hardy where you live, keep the pot somewhere cool and frost free instead.

3. 03

   Lavender in the ground

   In the ground, the soil decides. Lavender won’t tolerate heavy soil that stays wet over winter. In heavy soil, plant it on a mound or in a raised bed so the roots don’t sit in the wet.

   Don’t plant lavender in winter. Young plants rot easily in cold, wet soil.

4. 04

   Watering and feeding in winter

   Keep the compost fairly dry in winter, because damp compost encourages root rot. Water a pot only when the top 5 cm (2 in) are dry. Use a pot with large drainage holes and compost with up to a quarter coarse grit.

   Lavender needs no feeding in winter. It prefers poor soil anyway.

5. 05

   Pruning before and after winter

   The main trim is in late summer, just after flowering: remove the spent flower stalks and about 2.5 cm (1 in) of leafy growth.

   In spring you can clip again if it looks untidy or has frost damage. Never cut into old woody stems, because lavender rarely regrows from old wood.

6. 06

   Tender lavenders in spring

   Lavenders kept frost free over winter, such as French lavender, can go out in mild weather, often from March or April, first during the day. Keep fleece ready for cold nights and bring them back in for frost.

7. 07

   Common mistakes

   Wet soil: lavender won’t tolerate soil that stays wet in winter and rots easily.

   An unprotected pot: the root ball freezes far faster in a pot than in the ground.

   Cutting into old wood: lavender rarely regrows from it.

   The wrong lavender outside: French and other tender lavenders need a frost-free spot.

Common questions