An herb plant has many uses. While often used for cooking, other common uses are making herbal tea, air freshening, beauty treatments, and herbal remedies for those feeling ill. Whenever an herb plant is used, certain parts of the plant must be harvested.
As an herb gardener who wants to utilize his or her herbal garden to its full potential, you must know when to harvest and when to use the different parts of an herb plant. For example, many herb used for cooking use the leaves and/or thin branches or stalks of the plant. Flowers can be used also, but once flowers appear leaves can no longer be used.
An herb plant, like any other plant has a goal of creating seeds in order to multiply during the next growing season. Once flowers appear, all the plant's energies go into blossoming and creating and fertilizing the seeds or seed pods. This process means the plant begins to neglect its leaves, and so the leaves lose their flavor or sometimes turn bitter. This is why it is important for you to know all the uses of your herbs, it will allow you to harvest almost everything.
When harvesting an herb plant, think about what you're going to use it for. In the beginning, only leaves and stalks will appear, and this is usually good for cooking, beauty and home remedies or making tea. You will only need a few leaves from plant at any given time, so be sure that you only take what you need and do not over-harvest. When an herb plant is over-harvested it can die. Look up recipes that require leaves of plants (most recipes usually require leaves only), and you can begin using your herbs!
Once an herb plant begins to flower you are given several choices. You can nip the flower at the buds, allowing you to continue using the leaves at full flavor. You can allow the flowers to bloom and harvest the flowers or petals themselves, allowing you to create other different dishes, other beauty and home remedies, and make other teas. Or you can allow the flowers to bloom and let the petals fall, allowing you to harvest the seeds that are left behind.
Flowers can be used for cooking and making potpourri (though good potpourri will use some leaves as well.) Seeds on the other hand can be used for next year's garden, when you replant, though some herbs, like caraway, are used for their seeds when cooking.
An herb plant generally has three different stages at which it can be used, and each stage will give different flavors and different uses. It's all up to the herb gardener where he or she would like to use the different parts of their herb plants.