Easy-to-Grow Herbs for the Landscape

The value of herbs has been known for centuries. They have been used as flavorings in foods and as medicines for ailments. In addition, herbs are used as ornamental plants in the landscape.

Herb gardens add interest to any landscape, with a wide array of characteristics such as form, aroma, and unusual foliage. Herbs are used as borders, accent plants, and hedges. Further selection is based on whether the growing site is sunny or shady, wet or dry.

Starting an Herb Garden

Most garden centers offer a broad selection of herbs for immediate planting in the landscape. Select healthy, vigorously growing plants. The roots should be white to greenish-white. Be sure not to plant the herb any deeper than it was growing in the container. Planting too deep may cause the roots to rot.

Choosing a Planting Site

Most herbs thrive best in well-drained soil, with a soil pH of 6.0 to 6.8. The growing area should be tilled to a depth of 8 to 12 inches. Although herbs are somewhat drought-tolerant, adequate soil moisture is required for vigorous growth. Annual herbs require higher available soil moisture than perennial herbs.

Increase the water-holding capacity of sandy soils by adding a 2-inch layer of organic matter such as compost, sphagnum peat moss, or pine bark. Till the organic matter thoroughly into the soil. Amend heavy clay soils with compost or pine bark; otherwise, beds should be constructed to provide internal drainage.

Fertilizing

A proper nutritional balance is important for proper growth. Get a soil test before fertilizing. Overfertilization causes succulent, or weak, growth. Succulent growth dilutes the concentration of essential oils, thus limiting the flavor and aroma of the herbs. On the other hand, inadequate fertilization will limit growth, resulting in stunted and weak plants.

Base your fertilizer on the soil test recommendations. If you did not do a soil test, apply a complete, slow-release fertilizer with a 1-2-2 or 1-2-1 ratio of N, P, and K in the spring and again in mid- to late summer.

Mulching

Mulch with pine bark, straw, or wood chips, being careful not to pile the mulch around the stem base.

Pruning

Tender herbs should be pruned to remove dead tissue in early spring before growth begins. Herbs valued for their young foliage should be pruned regularly during the growing season to encourage fresh, young growth.

Harvesting

For foliage with the maximum amount of oil, harvest in the early morning, after the dew has dried. If this is not convenient, harvesting may be done anytime. To allow adequate time for regrowth of perennial herbs, do not harvest rigorously after late summer.

Mississippi Medallion Herb Selections

As a tool for promoting Mississippi-grown plants, the Mississippi Nursery and Landscape Association (MNLA) established the Mississippi Medallion Program in 1996. The purpose of this program is to identify plants that perform exceptionally well throughout the state and to promote the proper use of these plants in Mississippi landscapes.

Selections are evaluated at research sites before being brought before a selection committee. This promotional program is a joint effort of the MNLA, Mississippi State University Extension Service, Mississippi Agricultural and Forestry Experiment Station, and Mississippi Plant Selections Committee.

In 2004, ‘Purple Ruffles’ basil (Ocimum basilicum) was chosen as the first Mississippi Medallion award-winning herb (Figure 1). Deep purple leaves are intensely fragrant and are highly attractive in both herb gardens and flower beds. This annual will reach 24 inches in both height and width in full sun. Plants should be spaced at least 24 inches apart to ensure ample room in the bed. Basil should be fertilized with light applications of 5-10-5 fertilizer every 4 to 6 weeks or after harvesting leaves. Suggestions for use include color in salads, herbal vinegars, and pesto sauce.

The Mississippi Medallion Selections Committee chose cardoon (Cynara cardunculus) in 2008 (Figure 2). A full-sun perennial, cardoon thrives in cool-season landscapes and is used similarly to kale, cabbage, or mustard. Cardoon reaches 2 to 3 feet tall and wide. It can reach 4 to 6 feet if allowed to reach bloom in early summer. Plants should be spaced 18 to 24 inches apart for the cool-season landscape. Cardoon is edible, but blooms are also well-suited for cut-flower use. Plants should be spaced 42 inches apart if grown for blooms.

Rosemary (Rosmarinus officinalis) was chosen as the Mississippi Medallion award-winning herb for 2016 (Figure 3). A woody herb suited for full sun, rosemary cultivars may be either upright or prostrate. In general, upright rosemary measures 24 to 36 inches in height. Prostrate, or creeping, rosemary measures 1 to 2 feet in height and 2 to 3 feet in width. Narrow, gray-green leaves bring fragrance and texture to the landscape. Small flowers appear in various shades of white to deep blue. Rosemary requires well-drained soil but is drought-tolerant after establishment.

Publication 3677 (POD-07-24)

Revised by Christine E. Coker, PhD, Extension/Research Professor, Coastal Research and Extension Center, from an earlier edition by Lelia Kelly, PhD, David Tatum, PhD, and Norman Winter, former Extension horticulturists.