Bring the rosemary in, then dry or freeze the rest

One frost can finish off the rosemary you babied all summer. Pot it up now, and put the rest of the herb bed in jars and freezer bags before it goes.

Rosemary moves inside

In the Midwest, rosemary often does not overwinter, so Illinois Extension treats it as a tender perennial and brings it indoors. Wisconsin gives two ways: sink the pot into the bed, or dig the plant 2 to 3 weeks before the first fall frost and repot it, per UW-Madison Extension.

Indoors, give it a cool, sunny, humid spot. A pebble tray with water helps, and so does misting. Rosemary, thyme and bay laurel may need a grow light for 12 to 16 hours a day, according to Iowa State Extension.

Keep the soil on the dry side, per Illinois Extension; UW-Madison says to keep it moist but well drained and calls overwatering the biggest cause of rosemary decline.

Brown tips do not mean more water. Illinois Extension warns that can bring root rot.

Dry the sturdy herbs, freeze the soft ones

Ohio State University Extension splits it by leaf. Dry rosemary, thyme, oregano, sage and lavender. Freeze basil, cilantro, parsley, dill, chives and mint.

To dry, cut in the morning just before the flowers open. Hang bundles somewhere dry with moving air, or use a dehydrator at 95 to 115 F for 1 to 4 hours. They are done when they crumble.

Dried herbs are usually three to four times stronger than fresh, so use less.

Hang bundles somewhere dry with moving air. They are done when they crumble.

To freeze, wash and dry the leaves, spread them on a baking sheet, then bag them. Or chop them into ice cube trays and cover with water or broth. Use them within 3 to 6 months. They go soft, so save them for cooked dishes.

Bottom line

• Bring rosemary indoors before frost and keep it cool, sunny and on the dry side, per Illinois Extension.
• Dry the sturdy herbs and freeze the tender ones, per Ohio State University Extension.
• Store dried herbs airtight in a cool, dark place, and use frozen ones within 3 to 6 months.

Your zone

• Zone 3-4: Rosemary is not reliably hardy in zone 6 or colder, so overwinter it indoors, per Illinois Extension.
• Zone 5-6: Rosemary is not reliably hardy in zone 6 or colder, per Illinois Extension, though UW-Madison Extension lists 'Arp' as hardy to zone 7a, possibly 6a with protection.
• Zone 7-8: Rosemary is winter hardy only to zone 8a, per UW-Madison Extension; 'Arp' is hardy to 7a.
• Zone 9-10: In Florida, UF/IFAS Extension says rosemary will thrive year-round, though it may need protection from freezes in colder areas of the state.

Sources

• Illinois Extension, "Rosemary" - https://extension.illinois.edu/herbs/rosemary
• Iowa State University Extension, "Can I grow herbs indoors over the winter?" - https://yardandgarden.extension.iastate.edu/faq/can-i-grow-herbs-indoors-over-winter
• Ohio State University Extension, "Food preservation: preserving herbs, freezing and drying" - https://ohioline.osu.edu/factsheet/hyg-5360
• University of Wisconsin-Madison Extension, "Rosemary" - https://hort.extension.wisc.edu/articles/rosemary-rosemarinus-officinalis/
• University of Florida IFAS Extension, "Rosemary" (Gardening Solutions) - https://gardeningsolutions.ifas.ufl.edu/plants/edibles/vegetables/rosemary/ Photo: P1090247(4x3)-Rosmarinus officinalis (41960388224) by Miguel Angel Masegosa Martinez, CC BY 2.0, via Wikimedia Commons, https://commons.wikimedia.org/wiki/File:P1090247(4x3)-Rosmarinus_officinalis_(41960388224).jpg Photo: Gyogynovenyek1 by Szalkijanos, CC BY-SA 4.0, via Wikimedia Commons, https://commons.wikimedia.org/wiki/File:Gyogynovenyek1.jpg