Popular herbs like basil, parsley and oregano are relatively easy to grow in the garden, planted either in the ground or in containers. Most herbs need plenty of light for vigorous and healthy growth; owing to mostly Mediterranean origins, many plants used as herbs are suitable for hot, dry locations. Starting herbs from seed can also add diversity to the herb garden, as only a limited selection of standard herbs are usually available in stores and nurseries.
Plants grown for use as herbs generally fall into one of three categories: annual, biennial or perennial. Familiar annual herbs include basil, cilantro and dill, which produce seeds before being killed back completely by winter frosts. Biennial herbs, such as parsley, angelica and caraway, grow on a two-year cycle in which the plant produces foliage in the first year, followed by flowers and seeds in the second year, after which the plant dies. Perennial herbs come back year after year and include rosemary, lavender, thyme and sage.
Care and Culture
Most herbs require copious amounts of sunlight to grow well. For strong, bushy growth, choose sites that receive six to eight hours of sunlight daily. For garden sites, herbs should be located in areas that drain well and are not subject to flooding or washing out during heavy rains. Most herbs do not require fertilization, as additional nitrogen dilutes the essential oils that give herbs their flavor. Though many plants are sold as transplants, some herbs are better started from seed because they do not tolerate transplanting, such as fennel, cilantro, dill and anise.
Herbs for Shadier Spots
Several herbs are suitable for planting in sites that receive four to six hours of direct sunlight daily. Examples include sweet woodruff, which is particularly well-suited for shadier sites and is frequently used as a groundcover. Pot marigold can also be planted in part-shade conditions, as can dill, angelica, anise hyssop, chamomile, lemon balm, peppermint and spearmint. Soils should be well-drained for plants to thrive.
Container Herb Gardening
For dirt lovers who lack a scrap of earth in which to dig, many herbs are well-suited to container gardening. Popular choices include basil, thyme, oregano, parsley and chives. Tender plants such as basil transfer well from outdoor containers to indoor conditions. Container-grown herbs, especially those growing in pots located outdoors, will always require more frequent watering than herbs planted in the ground. Pot-bound herbs benefit from a high-quality potting soil that incorporates a slow-release fertilizer. To prevent plants from becoming thin and leggy, make sure they receive generous amounts of strong sunlight, though many plants will benefit from some afternoon shade.
Gardeners who allow their herbs to flower can save the seed for next year's planting, provided the plants are not hybridized. Species plants, or plants that have not been crossed to produce a desired trait, such as anise hyssop (Agastache foeniculum), will produce offspring from seed that have the same qualities as the parent. A hybrid plant, such as anise "Blue Fortune"---a cross between A. foeniculum and A. rugosa---will produce offspring whose traits are not identical to its parents or "true to type." In most cases, plants that are named cultivars are not suitable for saving seed.