Sage, a primary ingredient in many poultry seasonings, adds a touch of foliage color to your herb garden year-around. Rosemary blooms intermittently throughout the year and, when combined with seasonings, makes flavorful rubs for meats. Other winter herbs include parsley, bay, mint, and thyme; each featuring unique flavors and visually appealing foliage. Although winter herbs are generally very low-maintenance, you should still keep an eye on them throughout the season. Many winter herbs continue growing in the winter months and require some basic looking-after to preserve their vitality.
An organic mulch provides adequate protection for winter herbs during low temperature to minus 20-degree Fahrenheit. Bark, sawdust, straw, and pine needles all work great for maintaining consistent soil temperatures at the herbs' root systems. These mulches also protect against heaving caused by freezing and thawing of soil. A 3- to 6-inch layer of mulch should be applied after the first hard freeze to protect roots against cold temperatures. Do not apply heavy mulch before freezing weather as this causes soil to become warmer, making herb plants less tolerant to lower temperatures.
Since herb grow during winter months is usually slow and minimal, you should reduce cropping on all herb plants. It is acceptable to harvest limited quantities from several different plants, but realize there's a limit to the amount you can crop before herb plants become affected. You could accidentally kill off winter herb plants by depleting their reserves, so avoid over-harvesting winter herbs. Don't expect to crop much from sage and thyme, but parsley is less affected by over-cropping. Be care not to over-harvest rosemary and oregano.
Your watering techniques in the summer and fall can determine the resilience of winter herbs during colder months. Herbs that suffer from drought in the summer and fall are weaker and less likely to endure the winter season than properly hydrated herb plants. It's especially important to water herbs during dry winters, particularly before a severe freeze, as winter herbs can lose moisture from their foliage on bright, sunny winter days. Do not expose winter herbs to excessive amounts of water, however, but just enough to keep their roots hydrated.
Since winter herbs exposed to standing water are significantly less tolerant to cold weather, it's essential to provide adequate soil drainage at the site of your herb plants. Proper soil drainage is especially important to Mediterranean herbs such as thyme and rosemary, which are adapted to warmer climates. Incorporating pine bark mulch around your winter herb plants can help promote soil drainage and prevent standing water. In addition, you can also transplant your herb plants into raised beds to increase their resistance to colder weather and avoid possible exposure to standing water.
These are just a few simple methods of caring for winter herbs during colder seasons. Since all herb plants are different, it's important to be sensitive to their individual needs. Properly caring for your winter herbs allows you to harvest the benefits year-around.