Good soil is a crucial component for growing healthy herbs, either in the ground or in containers. Herbs receive the energy they need for growth and reproduction from the sun, but many of the components they use to carry out these sun-driven chemical reactions are derived from the soil in which they are planted.

The makeup of the soil determines a plant's water, nitrogen and phosphorous content, as well as its alkalinity, acidity and much more. Keeping all these factors in the proper balance is of utmost importance to the health of your herbs. Plants grown in outdoor soil have nature on their side and may require only a little bit of assistance from the gardener. On the other hand, the soil makeup present in a container garden is completely determined by the grower and may be altered to suit the needs of particular plants. Lavender likes good drainage and dry, alkaline soil, and sage can suffer root rot if the soil is kept too wet.

The needs of your plants should determine the type of soil you grow them in. Soils may range from sandy to clay-like, with many variations in between. Soils that are rich in clay tend to hold and retain water, while sandy soils, made up of glass-like particles called silicates, allow for better air flow and allow water to drain through them easily.

Most herbs are happiest with a mix of both soils, and you can vary the mixture to suit your particular plant. Sage, for example, likes drier, sandier soils, while peppermint thrives in a moist, clay-rich soil. A good compost can help with the soil balancing act.

Both airborne and underground pests are a consideration when growing herbs, but the proper soil maintenance can keep your plants strong enough to deter most of them. In fact, many herbs are pest-resistant when properly cared for.

Planting chives, mint, basil and cilantro around your roses and vegetables can help keep aphids away, and basil can also stave off tomato hornworm attacks. Sometimes, though, the balance becomes more tricky, and you must determine what you want to attract and repel. If you want to keep beetles away, dill and yarrow will attract the parasitic wasps that feed on them, but then you have the wasps to contend with.

Because tomato hornworms also love dill, the herb is often used as a "trap crop," meaning you can grow it so that the worms will eat it instead of your tomatoes. Of course, using this method ensures your dill won't last very long. Many herb gardeners deal with such dilemmas by carefully using pesticides that harm the pests that certain herbs attract. These chemicals must be used carefully, though, if you plan to use your herbs as food seasonings. Even pesticides deemed "safe" on house plants can accumulate to toxic amounts over time.

So perhaps your best bet to fend off herb pests is to keep your plants strong and healthy through proper soil maintenance.