For the culinary-minded gardener, herbs are not only aromatic and flavorful but also relatively simple to grow. They can be grown successfully in containers (indoors or out) or mixed strategically in your vegetable garden, where they will contribute to the repast and may help to repel unwanted insects. They can also mix in effortlessly with your perennial garden and some can find a good home by poking through crevices in stones walls or in openings between pavers and stepping stones.
Herbs can serve many functions in the garden. Take, for example, oregano (Origanum vulgare). The culinary varieties provide an exquisite light flavor that is perfect for cooking. There are also highly decorative ornamental oreganos such as ‘Herrenhausen’ and ‘Hopley’s’. These are for the designer and not the cook. Mix them with edible pot marigolds (Calendula officinalis) to create an appealing display.
Many herbs are both useful and ornamental. Sage (Salvia officinalis) comes in a variety of colors and variegations. There is purple sage (Salvia officinalis ‘Purpurea’), tri-colored sage (Salvia officinalis ‘Tricolor’) and variegated golden sage (Salvia officinalis ‘Aurea’). You can use these for cooking, as a garnish, and as a decorative component in your garden.
Some herbs such as sage (Salvia), tarragon (Artemisia dracunculus) and thyme (Thymus) are perennial in the Northeast and will last for several years; while others such as basil (Ocimum basilicum), sweet marjoram (Origanum majorana) and parsley (Petroselinum) are either annuals or biennials that are treated like annuals.
Basil is not frost hardy and should only be placed outside in mid-May in the New York area. Chervil (Anthriscus cerefolium) and coriander (Coriandrum sativum), on the other hand, welcome cool weather and should be sown early in the season. They will quickly go to seed and are well-suited to multiple sowings.
Some herbs thrive in containers. Mint (Mentha) excels in containers, which cleverly curb its invasive or aggressive nature. In the open garden it will spread uncontrollably. If you plant mint in the ground consider using either a barrier or plant it in a large plastic container that you sink into the ground. When choosing mints, peppermint (Mentha x piperita) is stronger, spearmint (Mentha spicata) is sweeter and pineapple mint (Mentha suaveolens ‘Variegata’) has wonderful variegated foliage.
Plants that like dry soil also thrive in containers. These include many of the Mediterranean herbs such as rosemary (Rosmarinus), marjoram and thyme. Use a lightweight porous potting mix and add a small amount of compost for organic matter. The container will prosper with watering, grooming (cutting back your herbs) and very little fertilizer.
Most herbs are probably better off without fertilizer; they like it lean. If you do fertilize, then give them a boost of diluted fish emulsion, liquid kelp or some liquid feed with low numbers, maybe once during the summer. Herbs tend to be more tasty and fragrant when they are not over-fertilized because they have a higher concentration of essential oils. The one exception to the rule is basil, which likes to be fed.
Make sure that you do not over-water your herbs. Most herbs like to be kept on the slightly dry side, otherwise they develop powdery mildew. Good drainage is also important. There are exceptions to this rule: basil, parsley, chives, horseradish and mint are a few herbs that can tolerate and even like moist soil.
Cutting your herbs back keeps them tidy and also supplies you with unsurpassed flavor for the dinner table. It is also good for the health of the plant, encouraging full growth and fresh tender shoots.
The best time to harvest herbs is just before they begin to flower, when the essence of the plant is strongest. Cut in the morning after the dew dries and before the hottest part of the day. Prune annual herbs back to about 1/3 - 1/2 their size and perennial herbs to about ⅓ of their size. Clean herbs in a bowl of cold water.
Herbs are versatile in the kitchen. Chop them up to give salads and vegetables extra flavor. If you are feeling adventurous, try making herb vinegar, herb butter, herb sugar or homemade pesto. Herb vinegars are simple: add herbs to good vinegar, steep for 4 to 6 weeks, and strain with a cheese cloth.
Fresh herbs often taste remarkably different from dried herbs. If you do want to preserve your herbs, an easy thing to do is to freeze them. Chop them up and place them in an ice cube tray with some water. Once they freeze, take the herb cubes out and store them in plastic bags for up to 6 months. To prevent basil from turning black, blanch the leaves by dunking them in boiling water for 1 to 2 seconds, then swirl them in a cold ice bath to stop the cooking process and dry them with a paper towel.
The old-fashioned way to dry herbs is by hanging them in a dry closet for 1 to 2 weeks. Faster methods include arranging them on a baking tray and letting them dry in an oven on the lowest setting for a few hours (check frequently) or placing them in the microwave for 3 minutes (check every 30 seconds). Once they are dry, store them in a glass jar for up to 6 months.
The best thing to do with herbs is to experiment with them in your garden. Silver lemon thyme (Thymus x citriodorus ‘Argenteus’) not only has nice variegated foliage but also a bright lemony flavor. Lovage (Levisticum officinale) is imperial in the garden and the leaves taste like celery. Summer and winter savory (Satureja), which have a fine robust fragrance, are used to flavor vinegars and beans or season fish and poultry.