To overwinter potted rosemary in a cold climate consider these steps. Firstly, prune the plant lightly to reduce stress and encourage compact growth. Place the pot in a sunny location, preferably near a south-facing window, ensuring it receives at least 6 hours of sunlight daily.
Place near a south-facing window.
Water the rosemary sparingly, allowing the soil to dry between waterings. This process is most successful if the plant is in a cool location ( near 60f / 15C ) and there is some humidity.
Often our homes are too dry and warm in the winter and don’t mimic the cool winter climate of the Mediterranean regions where the plant originates.
I’ve found that erring on the cool side results in less work and good success too. If you have an unheated garage that stays (mostly) above freezing you can overwinter this plant in a state of dormancy with minimal watering from November until early April at which time it can go back into the garden. I’m lucky enough to have a window in the garage but if temperatures remain at “refrigerator ” levels and the plant stays dormant I don’t think a window is necessary. I may pop a plant in the beer fridge one winter to test this theory. Hopefully it doesn’t end up being mistaken as some sort of Christmas garnish!
Not the best location for overwintering rosemary in this climate.
Advice and Photos by Victor Freiberg