Origanum

( oh - RIG - ah - num )

At-A-Glance Information

This genus includes species of herbaceous perennial plants and subshrubs native to Europe, Asia, and North Africa. Plants are strongly aromatic and produce profuse flowers in spring and summertime that are favorites of bees and other pollinators. Species in the genus are typically used as ornamental plants or added to vegetable or herb gardens. Use these woody plants throughout the landscape to add interest, scent, and flowers to mixed beds and borders, or grow them in containers.

Origanum Species and Varietals

The genus Origanum is a member of the plant family Lamiaceae, and includes 54 species. Plants in the genus are closely related to those in Thymus (Thyme), Mentha (Mint), Salvia (Rosemary), Satureja (Savory), and Ocimum (Basil). The ideal growing zones for these plants are USDA hardiness zones 4-10, though this will vary depending on the species cultivated; for more information, consult the descriptions below. To find your zone, click here: Zone Map.

Origanum amanum (Amanus Oregano, Amanos Kekiği)
This species, native to Turkey, forms an evergreen subshrub that reaches between 4 and 8 inches tall and a foot wide. Leaves are strongly aromatic, and clusters of pink flowers appear in summer and fall. These plants are used as culinary herbs or as groundcovers for sunny areas of the landscape. The specific epithet refers to the Amanus Mountains in Türkiye, where the plant is commonly found. Best in USDA zones 8-10.

Origanum dictamnus (Dittany of Crete, Cretan Dittany, Hop Marjoram, Diktamo, Eronda)
This tender perennial reaches between 8 and 12 inches tall when mature, and is native to Crete, Greece. It is used as a food flavoring, and is also grown as a landscape ornamental in gardens. Foliage is covered in soft grey-white hairs and has a velvety texture. Flowers are tiny and rose-pink with bright purple-pink bracts. This species performs well in USDA hardiness zones 7-10.

Origanum laevigatum (Ornamental Oregano, Herrenhausen Oregano, Hopley's Oregano, Smooth Oregano)
Best in USDA hardiness zones 5-9, this species grows from a woody base, and produces strongly aromatic leaves and loose clusters of pink-purple flowers with purple bracts that last through the summer months. It is native to Cyprus, Turkey, and Syria, and is used as a culinary herb and as a groundcover. Cultivars include 'Rosenkuppel' and 'Herrenhausen'.

Origanum libanoticum (Lebanese Oregano, Hopflower Oregano, Cascading Hopflower Oregano, Ornamental Oregano, Cascading Oregano)
This species is prized for its attractive foliage as well as its pink bracts and flowers which bloom from summer through fall. These small perennials reach up to 12 inches tall and a bit wider, and leaves are fragrant. Flowers are great in dried arrangements. Lebanese Oregano is suited for USDA hardiness zones 5-10.

Origanum majorana (Marjoram, Sweet Marjoram, Knotted Marjoram, Pot Marjoram)
This species is native to Cyprus, the Mediterranean, Turkey, Western Asia, the Arabian Peninsula, and the Levant. It produces smooth leaves and is considered a tender perennial. This species is typically grown in pots, as it has a tendency to spread prolifically and take over areas of garden. Leaves are used as a seasoning for soups, stews, salads, sauces, teas, and sausages. Best in USDA hardiness zones 9-11.

Origanum onites (Cretan Oregano, Greek Oregano, Pot Marjoram, Elliniki Rigani)
This species is native to Sicily, Greece, and Turkey, and has similar flavoring to common oregano. Flavor is a bit spicy, and is great for adding to pizzas. Both leaves and flowers are used fresh and dried; the best flavor is held within unopened flower buds.

Origanum rotundifolium (Round-Leaved Oregano)
This flowering plant is native to Turkey, Armenia, and Georgia and is a small, woody-based perennial plant that reaches up to 12 inches tall and just as wide. Leaves are strongly aromatic, and loose clusters of pink flowers bloom through the summer months. This species is used as an ornamental groundcover plant as well as a culinary herb in gardens.

Origanum syriacum (Bible Hyssop, Biblical Hyssop, Lebanese Oregano, Syrian Oregano)
This species is the primary ingredient in the spice mixture Za'atar. Plants reach a bit over three feet tall when mature, and produce small white to pale pink flowers in summertime.

Oreganum vulgare (Oregano, Wild Marjoram)
This species is a very popularly cultivated herb around the world, and is native to the Mediterranean region. It forms a woody plant that reaches up to 31 inches tall and produces white, pink, or light purple flowers on erect spikes in summertime. This species is considered invasive in New England, the Pacific Northwest, and Hawai'i in the United States. Cultivars are listed and described below:

'Aureum'
With golden foliage (best color in full sun) that has a mild taste.

'Greek Kaliteri'
Forms a compact, hardy plant with silvery-haired leaves with purple undersides. Pungent flavor.

'Hot & Spicy'
Highly aromatic scented leaves that have a spicy flavor. Great for pizzas.

'Nana'
Mature height is just 10 inches tall for these plants.

Caring for Origanum

Origanum, or Oregano, plants are typically planted via seed or as starts from a reputable nursery. Seeds can be direct-sown in the garden, or be started indoors between 6 and 8 weeks before the last frost of your area passes by. Plant Oregano in a spot that gets full sun; ideally, these plants like between 6 and 8 hours of sun each day. Some varieties, especially those with lighter or golden foliage, need more shade to prevent their leaves from getting sunburned. Ensure that soil is well-draining, rich in nutrients, and has a pH of between 6.0 and 8.0 (slightly acidic to slightly alkaline). If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Apply a layer of mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water new plantings regularly as they establish a strong root system in their new home. Once established, Oregano can tolerate moderate drought, and needs about an inch of water each week. Allow the soil to dry out between waterings, as this can go a long way in preventing root rot issues.

Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. These plants are not heavy feeders, and this should be sufficient to provide the necessary nutrients for the active growing and flowering seasons. Pruning is simple; remove any damaged, diseased, or dead foliage at any time during the growing season. Remove flower spikes as they form, as this will send more of the plant's energy into creating and maintaining flavorful foliage. Origanum plants are perennials, dying back each winter and regrowing the following springtime. They can survive in the landscape for 4 to 6 years before needing to be replaced. In areas where they are used as annuals, they are composted at the end of the growing season and replaced in the next with new plants.

Harvesting Origanum
Origanum, or Oregano, plants are typically grown for their fragrant, tasty foliage. Plants can be harvested beginning when they are between 6 and 8 inches tall. Harvested leaves can be used fresh, dried, or even be frozen for later use. Dried Oregano is a convenient herb, but the drying process does cause some flavor to be lost. Frozen Oregano has a stronger flavor but a somewhat odd texture, and is best in cooked dishes like soups and pasta sauces. Remove leaves individually or by stem using a pair of sharp, clean shears or snips. The best time of the day to harvest Oregano foliage is in the morning, after the dew has dried but before the heat of the day sets in.

Disclaimer: Information contained on this website is strictly and categorically intended as a reference to be used in conjunction with experts in your area. Foraging and consumption of plant parts should never begin without the guidance and approval of a local plant specialist. The providers of this website accept no liability for the use or misuse of information contained in this website.

Propagation

Origanum, or Oregano, can be propagated by division, cutting or seed. To ensure that your propagated plant will have the exact same qualities and characteristics as the parent plant, use the division or cutting method. If you would like to experiment and see what plant you can grow from seed, just keep in mind that it will not necessarily be the same as the parent plant, especially if you are propagating a hybrid cultivar. To propagate your Oregano or Marjoram, follow the instructions below:

Propagating Origanum by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. The best potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
Harvest your seeds. The seed heads on plants are pretty easy to spot, they're left behind after flowers have faded. Once they have dried out and begun to split open, you can harvest the seeds inside. Cut them off of the plant, placing them in a paper bag. Harvest as many as you can, and place the paper bag in a dry, cool, dark area. They will continue to split open and release the seeds contained inside. Once they have been released, take them out of the bag and put them in a container so you can work with them.
Get your container prepared. Water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 2-6 weeks from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots, filled with the same potting medium as described in Step 1. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 65 and 72 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.

Propagating Origanum by Cutting

Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. A good substrate for propagation of cuttings is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
In early summertime, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Cut one or more 5 inch portion(s) of the end of a non-blooming branch and strip the leaves off of the lower half. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about four to six weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots.
Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new plant.

Propagating Origanum by Division
This type of propagation is relatively simple; you will need a clean shovel, mulch, fresh soil, compost and pots (only necessary if you will be saving divided plants for transporting elsewhere). Division is best done in very early spring (after the plant has entered dormancy, but before it has begun its new spring growth), and needs to be done every few years regardless of whether you have the goal of propagating the plants for best performance. To propagate by division, follow these steps:

Using a shovel, dig up your existing plant. Start from the outside and work your way in to avoid damaging the root(s). Once you have worked it up out of the ground, lay it out.
Start to tease apart the roots with your fingers. Once the roots are somewhat untangled, separate your plant into segments, ensuring that each one has at least one thick root section attached.
Prepare your pot(s) or new planting site(s) with amended, well-draining soil. You can either bring in new soil or simply amend your existing soil with compost to complete this task. Then, plant your divisions and water thoroughly.
Apply a thick layer of mulch around the new planting to protect the root system from cold temperatures as it acclimates to its new home. Then, enjoy watching it sprout in the next growing season.

Origanum flowers fade, revealing seed heads that drop seeds.

Origanum seeds are very small, and typically dark reddish-brown.

Problems and Pests

Certain Origanum species are considered invasive in some regions; see the species descriptions above for more information. Check with local authorities before planting. Origanum, or Oregano, plants are susceptible to developing issues with the following pests and diseases in the landscape: