Q: I buy herbs every year thinking they will come back, but they don’t—why? —Teresa McHargue
A: For Kentucky gardeners, some herbs are considered perennials, and others are annuals or marginally hardy. Depending on the specific herbs, the answer could simply be that they are not hardy and need to be planted annually. Each herb is different in terms of hardiness, and in some cases, it differs between specific variety or cultivar.
For example: all lavender can be grown in Kentucky during the warmer months, but not all lavender will survive our winters. ‘Hidcote,’ ‘Munstead’ and ‘Provence’ are all hardy for us, given proper growing conditions. The same is true for rosemary. ‘Arp’ is a variety that can be grown as a perennial in USDA Plant Hardiness Zones 6-10. Check the grower’s tag for detailed information, including the hardiness. Kentucky is considered Zones 6b-7a.
Growing conditions are just as important as plant choice. In general, herbs thrive when grown in six hours or more of direct sun and well-drained soil. The most common perennial herbs for us are thyme, oregano, sage and mint. For a detailed list of culinary herbs for Kentucky gardeners visit www.ca.uky.edu for the publication, search “Culinary Herbs 74.”