Last Herb Harvest on the Balcony: What Needs to Come In Now
The first night frosts are on their way. Which herbs to harvest now, which can stay outside, and how to capture their flavor for winter.
Late October is decision time on the balcony: some herbs shrug off frost, others don’t. Sort them once now and you get one more good harvest, plus something in a jar, the freezer or a drying bundle for winter.
Who Tolerates Frost and Who Doesn’t
Basil is the most sensitive herb on your balcony: at temperatures around 5 to 8 °C it stops growing, and frost ends it. Lemon verbena and marjoram don’t like the cold either. You can overwinter lemon verbena indoors in a bright, frost-free spot. Parsley, chives, thyme, sage, oregano and mint, on the other hand, are hardy and can stay outside.
Rosemary sits in between: it tolerates light frost, but in harsh locations or a small pot a sheltered, bright and cool spot is the safer choice.
Basil: Harvest Now, Don’t Wait for Tomorrow
Cut all the shoots before the nights get colder. Frost-damaged leaves turn black and taste bitter. Basil loses almost all of its aroma when dried, so another route pays off: blend the leaves with a little olive oil and freeze the paste in ice cube trays. That gives you portions of a pesto base all winter.
Sage, Thyme, Oregano: Drying Pays Off
These firm-leaved herbs keep their aroma well when dried, and thyme and oregano even get more intense. Cut short sprigs, tie them into small bundles and hang them in a dry, airy, shady spot indoors. Outside, the October air is often too damp and the bundles can turn moldy. After one to two weeks the leaves rustle and strip off easily. Store them in a screw-top jar, dark and dry.
Don’t cut the plants back completely: leave enough green on them so they can get through the winter.
Parsley and Chives: Freeze Instead of Dry
Both taste flat when dried. Chop them finely instead and freeze them in portions, either pre-frozen loose on a tray or with a little water in an ice cube tray. The plants themselves stay outside in their pots and will sprout again in spring.
Winterproofing the Pots
For the herbs that stay outside, the biggest risk isn’t frost but waterlogging. Put the pots on small feet so water can drain, and move them close to the house wall. A layer of leaves or burlap around the pot protects the roots from freezing through. Water only on frost-free days, and sparingly.
Look It Up in the Plant Encyclopedia
You can look up how much cold a herb can take in the Rootivo plant encyclopedia, on the page for each plant. That way you don’t have to guess before the first frosty night.