It's little wonder that herbs have earned a place in American gardens. Freshly harvested herbs have pungent and aromatic qualities that far exceed those of their commercially obtained counterparts - whether fresh or dried. Even after the outdoor growing season is over, you can still enjoy dried herbs in fragrant potpourris and sachets. You will enjoy growing herbs because their culture is easy. They require little care and space, have very few insect and disease problems, and generally require only moderate fertility levels. Above all, herbs provide you with a continuing and satisfying hobby.
Here's a breakdown of what you need to know...
Choosing a Growing Site
Herbs flourish under the same conditions that you provide for your flower or vegetable garden.
Sun
Although most herbs will grow in partial shade, it is better if the herb garden receives at least 4 to 6 hours of direct sunlight a day. The more sun the better!
Soil
A majority of herbs will grow well under a wide range of soil conditions, with the exception of extremely wet, poorly drained soils. Note, however, that sage, rosemary, and thyme require a very well-drained but moderately moist soil. If the garden soil is poorly drained, you can improve the situation by modifying or amending the soil. Even more effective would be the use of raised beds.
In general, herbs do better in soils of low to medium fertility. So, when preparing the soil in your herb garden, additional fertilizer applications are not needed. Soils with high fertility tend to produce lots of foliage that is low in flavor. Prepare your garden site in the same manner that you would a vegetable garden, turning or tilling it to a depth of 6 to 12 inches. To improve soil fertility and porosity, add several cubic feet of potting or planting soil per 100 square feet of native soil before planting. Till or turn it into the soil thoroughly. Then level and rake the site to remove any large clods and debris.
Choose a Garden Type
Decide on a type of garden. An herb garden can take any form: formal, informal with flowers, trees, and shrubs; or in theme gardens.
Formal Herb Garden
A formal herb garden generally is composed of a series of beds that are not identical but appear balanced. The herbs are arranged by height, foliage color, and/or use, often in rows. Wide walkways are used to separate the beds and give the garden a sense of spaciousness.
Formal gardens of the 16th century were designed as knot gardens, as pictured above. This style used plants to create intricate, geometric designs within a square or rectangle. The designs were often edged with low-growing hedges of lavender or boxwood that showed off the subtle characteristics of the herbs. When choosing plants for a knot garden, select those that are compact, low-growing, and are manageable. Some suggested herbs are thyme, germander, rue, hyssop, rosemary, and santolina. Avoid invasive herbs such as the mints. In addition to the herbs, statuary, topiaries, and container-grown plants are important features to include in a formal garden.
Informal Herb Garden
Herbs are often informally combined with annual and perennial flowers, trees, shrubs, groundcovers plants, vegetables, or other plant materials in an informal garden. This allows you to take advantage of the various colors, textures, sizes, and shapes that other plants have to offer.
Herb Theme Gardens
Some gardeners prefer to select a specific theme for their herb garden and choose the herbs accordingly. Some examples are a kitchen garden (including thyme, sage, basil, tarragon, dill); a single color garden such as gray-green (including horehound, lavender, artemesia, and wormwood); a scented garden (including mint, scented geranium, lemon balm, silver thyme, and rosemary); or a garden with different varieties of a specific herb (common sage, Tricolor sage, golden sage, purple sage, clary sage, pineapple sage). The possibilities are limited only by your imagination.
Don't limit your use of herbs to specific situations. You can use them to enhance most any garden. Of course, some grow better as groundcovers, others as edging plants; still others are best when intermingled with different plants in a mixed border. Most, however, are best used where their fragrance and beauty can be appreciated up close.
Garden Design
Put your ideas on paper. Once you have decided on the type of garden you want, make a rough sketch or drawing on paper. This helps to visualize what the garden will look like and will help in figuring the number of plants needed. Think about the staging (shorter plants in front, taller towards the back) as well as succession of flowering. It is much easier having it on paper than trying to remember it.
Size
The size of your garden will depend largely upon the quantity of herbs that you need and want to grow. A dozen annual and/or perennial herb plants will provide you with a good variety.
Color
Consider color schemes and combinations. Use specific plant characteristics when deciding where to locate the plants. Color is one of the most noticeable features of a plant. By choosing a single color scheme, you can create a garden that gives a sense of space, openness, and brightness. For greatest effect, vary the height, shape, texture, and size of the flowers and tones of the color. Colors can also be used in combination; some colors blend together better than others. For example, a plant with silver-foliage, such as horehound or artemisia, enhances a red or pastel foliage or flowers. Yellow and blue is always a good combination. Orange and blue, yellow and violet, and red and green are complementary colors and create a strong effect.
Contrast
Another technique to use to make your garden more interesting is contrast. By definition, contrast is using opposing elements close together to produce an intense or intriguing effect. You can contrast textures, darks, lights, colors, shapes, lines, flower form, flower height....any design element. For example, rounded plant forms look best next to those that are upright; a plant with round flowers is complemented by a plant with spiky flowers.
Texture
The foliage of a plant gives it its texture. Think about the foliage texture of a particular plant and how it contrasts with the texture of another plant. Plant soft leaf textures next to those with shiny or rigid leaf texture. Plant small, dense-leaved plants next to those with a more open and airy habit.
Plant Placement
Keep the herb plants together. It is very important to define the garden. If you want more than one of a plant in the garden, such as sweet basil, rather than scatter them throughout the garden, it will look better to keep them together in a grouping.
Edging
Edging the herb garden with stone, wood, brick or some other type of edging is optional, however, defines the planting area and makes the garden look as though it belongs in the landscape. If the plants are located next to a wall, a sidewalk or path can provide the boundary. If they are located in a lawn area, a permanent edging of brick or wood can be useful. A defined area looks more "finished" and is easier to maintain.
Other Features
In addition to the plant material, other things to consider placing in the herb garden are benches, sculptures, and other objects that serve as focal points or enhance the planting.
Herb Garden Care
Your herb garden will need attention throughout the growing season. Weed control and provision for adequate moisture are two important cultural necessities. In the absence of rainfall provide additional moisture. The use of a mulch is an attractive and effective means of controlling weeds and maintaining constant soil moisture and temperature for the root systems of your herbs. Mulches that you might consider include bark chips or shredded bark, compost, ground corncobs, pecan hulls, or dried grass clippings. To be effective, the mulch should be applied at least 3 inches deep around the plants.
Here are some suggestions to ensure plant survival:
Avoid late feeding
Most herbs are more flavorful when the fertility is not too high. Late feeding of plants might force new growth that could be damaged by a frost. Cease fertilization two months prior to the first frost date in your area.
Avoid late pruning
Pruning should be done during spring and summer; avoid excessively cutting the plants back in the fall. The growth serves to catch leaves that help insulate the plants.
Avoid wet soils
Though some herbs tolerate poor or wet soils, the majority prefer to grow in well-drained soils. Herb plants in overly wet soils will grow poorly and are subject to root rot. Heavy clay soils, which tend to hold more water than other soils during winter, should be amended with organic matter to loosen the clay structure. Alternatively, you can plant your herbs in raised beds to lift their roots above the water table.