Rosemary is a real plant from the Mediterranean coast: sun-hungry and absolutely in need of warmth. Most rosemary varieties are very sensitive to frost; there are only a few winter-hardy rosemaries. That's why rosemary should only stay outside in mild winters and otherwise, ideally, overwinter in a pot in cold house conditions.
How to overwinter rosemary?
To overwinter rosemary successfully, plant hardy varieties outdoors with frost protection such as brushwood or insulating mats, or store rosemary in a pot at 4-12°C, in a bright location and with occasional watering without fertilizing.
Wintering rosemary outside
Only hardy varieties such as Veitshöchheim rosemary, “Arp” or “Blue Winter” should overwinter outdoors, as well as older plants from their third year onwards. These are the ones that are so well anchored in the ground by their roots and robust enough to withstand lower temperatures with the appropriate protection. You can protect the plants from frost as follows:
- Cover the soil in the root area and the plant itself with fir or spruce branches.
- Provide a tight covering, but at the same time ensure sufficient air circulation.
- The bottom area can also be covered with leaves as the bottom layer.
- Plant the rosemary in a sunny and protected location, preferably facing south.
- A spot on a house wall that gives off heat is ideal.
- Instead of brushwood, you can also cover the plant with insulating mats (€25.00 on Amazon).
- However, these should be permeable to air and light so that no waterlogging can form.
- Rosemary is also evergreen and needs sun even in winter.
Overwintering rosemary in a pot
Potted rosemary overwinters best under cold house conditions at temperatures between 4 to 12 °C in a bright location indoors. A bright stairwell, a place in a garden or greenhouse, in the basement or in a (slightly) heated bedroom are ideal for this. You should water the plant occasionally, but not fertilize it. In a protected place and if it is a mild winter, the pot can also be left outside - wrapped in protective film and covered with brushwood.
Tips & Tricks
Rosemary that overwinters outdoors should not be pruned. It is therefore advisable to harvest and preserve plenty of fresh rosemary in the summer.
