Trim herbs as you use them or prune as needed with snips or shears. Even in hedges, keep plants far enough apart for good air circulation. Whenever pruning, lay a piece of plastic, paper, or cloth beside and beneath the plant to catch the clippings. You can often use them for potpourris, mulching garden paths, adding to the fireplace for fragrance or to the grill for flavor.
Below are a few tips for pruning various types of herbs.
1 - If you sow your herbs from seed in the garden or in containers, make sure to thin the seedlings out spacing them as indicated on the seed packet.
2 - Harvest leaves and flowers of herbs in the morning.
3 - Don't cut an evergreen herb, such as Rosemary, back by more than 1/3 in Fall.
4 - Annual herbs, such as Basil should not be allowed to flower. Snip of flower stems before they bloom to develop best aroma and flavor
5 - Allow Coriander/Cilantro to flower if you intend on harvesting seeds. If not, remove flower stems as soon as they appear.
6 - Herbs growing closely together should be pruned/sheared frequently to allow for good air circulation.
7 - Perennial herbs should be cut back in late Winter.
8 - Soft perennials, such as germander and oregano benefit by being cut back by 50% of their size during the rainy season.
9 - Thyme should be cut back in the Fall to maintain bushiness.
10 - Let lavenders grow freely throughout the Summer and then cut them well back at harvest in early Fall.
11 - Allow the caterpillars to prune your fennel if you want them to turn into butterflies.
