For the most part, herbs do not require the fertile soil conditions we lavish on our prized ornamentals, since many originate in environments where the soil is on the lean side. Overfeeding herbs tends to cause their growth to be soft and lanky, and actually lessens the amount of essential oils that give them their special culinary qualities.
Whenever plants are container-grown, however, watering eventually causes many of the nutrients to leach out of the growing medium, and fertilizing becomes necessary. For an organic approach to fertilizing, make a compost "tea"
Compost Tea How-To
1. Shovel some compost onto the middle of a two-by-two-foot square of burlap, and tie the corners together with twine.
2. Soak in a plastic or galvanized-steel bucket for a couple of days until the water turns a rich, brown color. Remove the burlap sachet, and empty its contents back onto the compost pile.
3. Use the nutrient-rich brown ''tea'' to water your herbs.