This herb frequently used in Italian cuisine has green foliage and a warm fragrance; it blooms small white, blue, or pink flowers in the summer. Oregano is a great starter herb because it’s easy to grow and tends to yield very well. Oregano has few pest and disease problems, but indoor plants can be susceptible to spider mites, especially during dry winter months. Oregano grown indoors in pots with the proper potting mix is much less susceptible to fungal root diseases than an outdoor plant grown in the garden.
Oregano Care
Light
Oregano thrives under bright light, so a bright window with morning sun is perfect. Alternatively, it can be very easily grown under standard or compact fluorescent lights, as well as halide lights. In general, the brighter, the better.
Soil
Oregano growing in a pot prefers airy, light, fast-draining soil. To mix your own soil that’s suitable for growing oregano indoors, you can mix potting soil with coarse sand or finely ground granite.
Water
Water oregano regularly, but not excessively. Let the soil dry completely between waterings. Oregano is naturally drought-resistant, making it a perfect indoor plant.
Temperature and Humidity
Oregano is a hardy plant that will thrive down to 50 degrees Fahrenheit and up to 80 degrees Fahrenheit or even higher. Oregano may react badly to the very dry indoor conditions found in winter, so you may need to provide extra humidity. One good method is to place the pot on a tray filled with pebbles that are kept moist over winter.
Fertilizer
Use liquid fertilizer, or supplement the soil with controlled-release pellets. For organic oregano, use an organic fertilizer or fortify the soil with compost. Some growers swear that the type of compost changes the taste of the leaves, so you may want to experiment with fertilizers. Pot-grown oregano that is watered frequently will require more feeding than do garden plants.
Oregano Varieties
Different types of oregano are used in different cuisines to get that perfect added flavor. They range from mild to rather spicy and strong. Here are a few popular varieties of oregano:
Origanum vulgare is the typical garden oregano. It’s used in pizzas and tomato sauces.Origanum majorana is less spicy than Origanum vulgare. This milder variety is often used in salads or for seasoning meats.Origanum syriacum is used in preparing za’atar, a spice mixture used to flavor Middle Eastern dishes.Origanum vulgare ‘Aureum’ is commonly called golden oregano, named for its intense yellow leaves. It has a mild flavor and can be used in cooking but this cultivar is known best for its visual appeal.
Harvesting Oregano
With an indoor plant, you can clip off leaves of oregano to use as soon as the plants are 4 to 5 inches tall. The easiest way to strip the leaves is to hold the stem by the top and run your finger down the stem. People used to the dried oregano in bottles will likely be surprised by the sharp flavors of fresh oregano—it has a wonderful flavor that is quite different from the dried supermarket product. Oregano is an ancient medicinal plant and its use as a therapeutic agent goes back centuries, when it was used for gastrointestinal and respiratory problems. Oregano can also be dried easily and stored or used to create highly flavored oregano oil.
Pruning Oregano
As with outdoor plants, oregano growing in pots should be pinched back regularly, starting when the plant is about 4 inches tall. This will prevent it from flowering, which makes the stems woody. If the plant becomes too woody, you can trim it back to the base to stimulate new, fresh growth.
Propagating Oregano
Like most other herbs, oregano is typically grown from nursery-raised stock or seeds. Growing oregano from seeds opens up a world of options for this tasty herb, as there are many kinds of oregano beyond the standard. If you have an existing plant, oregano readily propagates from leaf cuttings. Remove entire leaves from the plant and suspend them in a glass of water until a good network of roots appears, then plant it in a pot filled with coarse, well-draining potting mix.
Potting and Repotting
Healthy oregano is a rapid grower and will quickly fill a pot. In general, it’s a good idea to cut the plant back once it begins to become unruly, which should also reduce the need for repotting. Also in general, don’t repot indoor herbs (even perennials). Instead, use them for a few months, then replace the plant when the initial soil begins to show signs of exhaustion, usually after about six months. Ideally, repot oregano just once, from the initial nursery pot (usually a 4-inch plastic pot) into a 6-inch clay pot when you first bring it home.