Growing Marjoram: The Sweeter Cousin of Oregano
Sweet marjoram's milder oil sets it apart from oregano, and one field trial suggests flowering changes that oil more than it spoils it.
Rub a leaf of sweet marjoram and a leaf of Greek oregano side by side and the difference is obvious. Marjoram is softer and sweeter, oregano sharper. The two are close relatives in the same genus, Origanum, and the gap shows up clearly in their oils.
Sweet marjoram’s oil carries only a trace of carvacrol, the compound that dominates pot marjoram and is a major compound in many Mediterranean oreganos. The plant is frost tender, grows readily from seed and is happy in poor soil. And the familiar rule that flowering spoils the leaves has less behind it than you might expect.
What makes marjoram taste sweeter than oregano?
Mostly a different set of compounds in the oil. A 2004 peer-reviewed study of Turkish material found the usual sweet marjoram type “poor in oil” with “only trace” carvacrol, led instead by sabinene hydrate and terpinen-4-ol. The paper also notes a second type of Origanum majorana in south-western Turkey, rich in oil and carvacrol, so the species name alone doesn’t guarantee a sweet plant.
Here’s how the main sources line up.
| Plant | What the oil is mostly made of | Hardiness |
|---|---|---|
| Sweet marjoram (O. majorana) | Sabinene hydrate and terpinen-4-ol, trace carvacrol (2004 study) | Frost tender |
| Pot marjoram (O. onites) | Carvacrol: 71% in a Turkish sample (2019), 48% in a Greek one (2019), which cites about 50% to 85% in earlier work | Slightly hardier than sweet |
| Oregano (O. vulgare) | Varies; among 502 European plants, Mediterranean ones leaned towards carvacrol/thymol-type or linalool-type oils, continental ones towards sabinene-type (2015 survey) | Hardy |
Hardiness follows the Royal Horticultural Society, which says oregano “tends to be hardier than marjoram.” Our post on Greek oregano covers the sharper herb.
Which one have I got?
Check the Latin name on the label, then look and smell. Common names overlap badly. The RHS makes a strong case for O. majorana as “the only true marjoram,” yet O. vulgare is also called wild marjoram, and NC State Extension lists pot marjoram among the common names of O. majorana itself. The RHS suggests buying plants in person “so you can check their aroma.”
- Sweet marjoram (O. majorana): soft, pale green leaves, which NC State describes as hairy and grey green, small white flowers and a delicate, sweet flavour. Mounds reach about 30 cm tall and wide in the RHS guide, and 30 to 60 cm (converted from 1 to 2 feet) in NC State’s.
- Pot marjoram (O. onites): green leaves with a stronger flavour, white flowers sometimes sitting on pinkish bracts (modified leaves), about 50 cm high and wide.
- French marjoram: new leaves of fresh golden green, a spicier, stronger flavour than sweet marjoram, about 45 cm across, and hardy in most UK gardens.
Does flowering really ruin the flavour?
Garden guides say pick early, and one trial complicates that. NC State says the leaves have their “best flavor before the small white flowers bloom,” and suggests cutting stems back before flowering to keep plants bushy. The RHS also says the flavour is best before the flowers open.
A 2009 peer-reviewed field trial in Lublin, Poland, cut sweet marjoram at two stages, as flower buds began to form and at full bloom. Across two seasons, herb cut at full bloom held more oil, 1.74% against 1.51%, which works out to about 15% more, and the harvest was larger too, though the full-bloom cut also came about three weeks later.
What changed was the mix. In 2007, the one season both stages were analysed, trans-sabinene hydrate fell from 25.42% of the oil at the bud stage to 14.39% at full bloom, while terpinen-4-ol and several others rose. The authors say weather shifted the mix as well. (The Polish oil was led by the trans form of sabinene hydrate, the Turkish study by the cis form.)
Some limits apply. It’s one site and one team, the oil was distilled from the air-dried cut herb, which at full bloom includes the flowers, and nobody tasted it. So flowering seems to change the make-up of the oil more than it drains it. Pinching buds still suits a kitchen plant you cut all season, because it keeps the plant bushy and leafy, and the flowers are edible anyway.
Can marjoram survive winter?
That depends on your winters. In frost-free and mild gardens, sweet marjoram can live on as a perennial. NC State rates it a tender perennial that “may not survive a winter north of USDA zone 9,” the mild-winter end of the US scale, and calls it a good choice for hot summers thanks to its drought and heat tolerance. The main risk there is wet ground, since it “will rot in poorly-drained, saturated soils.”
In cold-winter gardens, plan to resow each spring, as the Polish trial did with its annual crop. Bringing a pot indoors is a bonus. The RHS suggests containers that can move to a sunny windowsill, conservatory or frost-free greenhouse in autumn, while NC State warns that potted plants brought in “usually do not overwinter well.” Our windowsill herbs guide covers light and watering indoors.
How do you grow marjoram from seed?
Sow indoors about 6 to 8 weeks before your last frost date, as NC State suggests. Scatter the tiny seeds thinly with no need to cover them, keep them at around 20°C, and go easy on water, because seedlings are prone to fungal disease, the RHS advises.
Plant out after your last frost, at least 20 cm from neighbours. Seed of sweet and pot marjoram is widely sold, though named varieties are harder to find. For an existing plant, layering, division and summer softwood cuttings all work.
Plants in the ground need no extra feed. Pots more than a year old benefit from a little general fertiliser.
How should you harvest and use it?
Snip shoots as needed and strip the leaves. Sweet marjoram is often used fresh, unlike oregano, and added near the end of cooking to keep its flavour. The leaves dry well too.
If you have cats or dogs, note that NC State flags sweet marjoram as a problem for both and says it “can be toxic for pets.”
What this means for you
- Buy by Latin name and smell. O. majorana is the sweet one; O. onites leans towards oregano.
- Keep it as a perennial in frost-free gardens, with sharp drainage, and resow each spring where winters are cold.
- Sow on the surface in warmth, 6 to 8 weeks before your last frost.
- Pinch buds to keep plants bushy, and don’t worry if a few flower.
- Skip the fertiliser for plants in the ground and give them full sun.
Do you grow sweet marjoram, pot marjoram or both, and can you taste the difference in your cooking? Hit reply and tell us.
How we made this: AI tools helped us research and draft this post. We checked every figure, quote and link against its original source before publishing. Figures are as of 8 November 2026.
Grown with intention by Dynamic Nexus Garden.