Oregano (Origanum vulgare)

Origanum vulgare is a heat-loving, pungent herb that is found in Mediterranean and Mexican cooking. Growing oregano indoors is an excellent way to bring those flavors to your food. If you are a dedicated cook, a display of fresh growing herbs in hand enhances your dishes and enlivens recipes. Planting oregano indoors can be done alone or in a trough with other like-minded herbs.

I. Appearance and Characteristics 

Oregano (Origanum vulgare) is a species of flowering plant in the mint family Lamiaceae. It was native to the Mediterranean region, but widely naturalized elsewhere in the temperate Northern Hemisphere.

Used since the middle 18th century, the Spanish word orégano is derived from the Latin orīganum which itself comes from Classical Greek ὀρίγανον (orī́ganon). The ultimate origin is disputed; some claim it is a compound Greek term that consists of ὄρος (óros) meaning “mountain”, and γάνος (gános) meaning “joy”, thus, “joy of the mountain” while The Oxford English Dictionary states it is “probably a loanword [as] the plant comes from Africa”, and that “joy of the mountain” is a false etymology.

Oregano is related to the herb marjoram, sometimes being referred to as wild marjoram. It has purple flowers and spade-shaped, olive-green leaves. It is a perennial, although it is grown as an annual in colder climates, as it often does not survive the winter. Oregano is planted in early spring, the plants being spaced 30 cm (12 in) apart in fairly dry soil, with full sun. It will grow in a pH range between 6.0 (mildly acidic) and 9.0 (strongly alkaline), with a preferred range between 6.0 and 8.0. It prefers a hot, relatively dry climate, but does well in other environments.

II. How to Grow and Care

Sunlight

Oregano loves the sun, so ensure that your placement has full sun for strong flavor. Offer partial shade if growing in hot climates.

Watering

Oregano doesn’t need quite as much water as most herbs. As the amount of watering depends on many variables, just water when the soil feels dry to the touch. Remember that it’s better to water thoroughly and less often.

If you have a container, water until the water comes out of the drainage holes in the bottom of the container.

Planting Instructions

Oregano can be grown from seed but is usually available in small herb pots or punnets. Before planting out or transplanting, always water the pot to minimize root disturbance and transplant shock.

Growing oregano in pots

• If growing your oregano in a pot, select a premium potting mix, preferably designed for herbs and veggies.
• Fill the pot and make a small hole in the center for your oregano. 
• Place it in the hole and firm the potting mix around the plant. It should be at the same height in the potting mix as it was in the previous pot. 
• Water and place in full sun.

Growing oregano in the garden

• Improve the soil with a little compost and composted manure prior to planting. 
• If the soil is prone to damp, either raise the level of the soil to improve drainage (build it up into a mound) or select another area of the garden to plant your oregano. 
• Make a hole large enough for your plant and carefully remove it from the pot by squeezing the sides of the pot and tipping it upside down.
• Place your fingers either side of the plant to prevent it falling out and becoming damaged.
• Plant in the hole and backfill, making sure it is still at the same height in the soil as it was in the pot. 
• Mulch to prevent weed growth and water well to settle the soil in around the roots. 

Pruning

Allow oregano plants to grow to about 4 inches tall and then pinch or trim lightly to encourage a denser and bushier plant. Regular trimming will not only cause the plant to branch again, but also avoid legginess.

To ensure the best-quality plants, thin out plants that are 3 or 4 years old in the early spring.

Propagation

Growing oregano from cuttings

• Take tip cuttings in spring. The cuttings should be about 6cm long. 
• Pinch your finger over the lower 2cm of the cutting and run your fingers downward to remove the lower leaves. 
• Dip the cut end in rooting hormone or cutting gel, and then insert it into a pot filled with propagating mix.
• Make a hole using a pencil to prevent loss of the rooting hormone at planting, then insert the cutting, firm down the soil, and water. 
• Place in a bright position and water when dry. 
• Roots will develop over the coming 6–8 weeks, at which time the plants can be repotted..

Layering oregano

Layering is an easy way to propagate oregano, and something this tasty herb does naturally. This occurs when a branch or stem touches the soil. This association with the soil and moisture causes the stem to send out roots, which establish in the soil, creating a new plant that can then be separated from the parent. To accelerate this process, peg long stems down and cover a small section with soil to promote root development.

Overwintering

At the end of the season, you can move pots indoors for the winter;  cut dead stems in the spring before new growth. In warmer climates, protect plants with mulch.

Pests and Diseases

Slugs and snails may be attracted to your oregano while it is young. Lay snail and slug traps to reduce any damage.

While some insects are said to be repelled by oregano, aphids are not one of them. If found, try removing them with a solid jet of water. If this does not work, spray the aphids with a soap spray or Eco-Oil.

III. Uses and Benefits 

• Ornamental uses

A hardy groundcover, oregano is a popular addition to herb gardens and as an edging plant in veggie patches and kitchen gardens. It’s also perfect for the urban farmer or budding chef who only has room for a few flavourful pots.

• Culinary uses

Oregano is a culinary herb, used for the flavor of its leaves, which can be more intense when dried than fresh. It has an earthy, warm, and slightly bitter taste, which can vary in intensity. Good-quality oregano may be strong enough to almost numb the tongue, but cultivars adapted to colder climates may have a lesser flavor. Factors such as climate, season, and soil composition may affect the aromatic oils present, and this effect may be greater than the differences between the various species of plants. Among the chemical compounds contributing to the flavour are carvacrol, thymol, limonene, pinene, ocimene, and caryophyllene.

Oregano is the staple herb of Italian cuisine, most frequently used with roasted, fried, or grilled vegetables, meat, and fish. Oregano combines well with spicy foods popular in Southern Italy. It is less commonly used in the north of the country, as marjoram is generally preferred. Its popularity in the U.S. began when soldiers returning from World War II brought back with them a taste for the “pizza herb”, which had probably been eaten in Southern Italy for centuries.

Oregano is widely used in cuisines of the Mediterranean Basin and Latin America, especially in Mexican cuisine and Argentine cuisine. In Turkish cuisine, oregano is mostly used for flavouring meat, especially mutton and lamb. In barbecue and kebab restaurants, it can be usually found as a condiment, together with paprika, salt, and pepper.

During the summer, generous amounts of dried oregano are often added as a topping to a tomato and cucumber salad in Portugal, but it can be used to season meat and fish dishes as well. In Spain, apart from seasoning, it is used in preparations of a variety of traditional dishes such as morcilla (Iberian pig blood sausage) and adobo sauce for fish and meat. The dried and ground leaves are most often used in Greece to add flavour to Greek salad, and is usually added to the lemon-olive oil sauce that accompanies fish or meat grills and casseroles. In Albania, dried oregano is often used to make herbal tea which is especially popular in the northern part of Albania.

• Other uses

Oregano oil has been used in folk medicine over centuries. Oregano essential oil is extracted from the leaves of the oregano plant. Although oregano or its oil may be used as a dietary supplement, there is no clinical evidence to indicate that either has any effect on human health.

In 2014, the US Food and Drug Administration (FDA) warned a Utah company, Young Living, that its herbal products, including oregano essential oil, were being promoted to have numerous unproven anti-disease effects, and so were being sold as unauthorized misbranded drugs subject to seizure and federal penalties. Similar FDA warning letters for false advertising and unproven health claims about oregano essential oil products were published in 2017 and 2018.

IV. Harvesting and Storage

• Harvest the leaves with sharp shears as you need them, once the plant is several inches tall. This will encourage new growth. Just don’t harvest more than one-third of the plant at a time.
• The most flavor-filled leaves are found in mid-summer, right before the flowers bloom.
• You can freeze the leaves to use during the winter. Oregano leaves store well and are easily dried. Keep them in an airtight container once dried.