Yes, you can grow marjoram indoors, and the whole thing comes down to light. Get the light right and the rest is easy. I keep a potted sweet marjoram on the sunny kitchen windowsill. Last winter it gave me fresh leaves for soups and roast chicken straight through the cold months. Growing marjoram indoors works once you treat one bright, south-facing window as the make-or-break factor. Pick that window first, and you have done the hardest part.
My first try went the other way. I set a little pot on a dim north-facing sill, and within a few weeks the plant stretched pale and floppy, reaching for light it never got. The stems went thin and the flavor faded to almost nothing. Same seed, same soil, same care. The only thing that changed was the window, and that one change decided everything.
Indoors, your marjoram wants the same things it wants outside. Give it about six hours of direct sun a day, a small pot with drainage holes, and a light, free-draining potting mix. Your pot size matters more than you think. A small pot dries out at a steady pace, and that steady drying is exactly what these Mediterranean roots like best. Skip a big pot, since the extra soil holds water your plant does not want around its roots. Match the pot to the plant and you avoid soggy soil from the start.
A south-facing window is your top pick for marjoram on windowsill growing, since it pulls in the most direct sun through the day. An east or west window can work if you have nothing better, but you will get a leggier plant. No bright window at all? A simple grow light fixes that fast. Run it for about twelve hours a day and set it a few inches above the leaves. Your plant will grow stocky and full instead of thin and reaching, and you can move it closer if the stems start to stretch.
Watering is where most people slip up with marjoram in pots. Wait until the top of the soil feels dry, then water until it runs out the bottom. Tip out anything that pools in the saucer so the roots never sit in standing water. Marjoram hates wet feet far more than it minds a dry spell, and that one habit makes or breaks growing marjoram indoors. So when you are not sure, leave your plant one more day before you reach for the can. Stick a finger in the top inch of soil if you want to be certain, since dry to the touch means it is time to water.
Feed your marjoram light during active growth and skip it the rest of the time. A half-strength liquid feed once a month through spring and summer keeps the leaves full of flavor without pushing soft, weak growth. Too much feed gives you fast growth that tastes of nothing, so go easy. Pinch the tips often too. When you snip the top of each stem, the plant branches out bushy, and you get more leaves to cook with. Pinching also keeps your plant compact and tidy on the sill.
Two mistakes kill most indoor plants, and both are easy to dodge. Too little light makes your marjoram leggy, with long bare stems and few leaves. Too much water rots the roots before you ever see it coming above the soil. So err toward more light and less water, and your indoor herb growing will pay you back. Watch for whitefly or spider mites on the undersides of leaves, and wipe them off with a damp cloth if you spot any. Get the light and water right, and a windowsill marjoram will feed your kitchen for months.
Read the full article: Marjoram Plant: Grow, Use, and Benefits
