8 Reasons why your indoor herbs are dying and how to fix it

Most indoor herbs die from one of two things: too much water, or not enough light. Everything else on this page is a distant third.

Start with the symptom you can actually see, then read the section it points to.

Start here: what does it look like?

What you see	Most likely cause	Go to
Drooping leaves, soil is damp	Root rot from overwatering	Water and drainage
Drooping leaves, soil is dry	Simple thirst, usually recoverable	Water and drainage
Yellow leaves starting at the bottom	Overwatering, or nitrogen shortage in old soil	Water, then fertilizer
Long bare stems, big gaps between leaves	Not enough light	Sunlight
Pale, washed-out leaves	Not enough light	Sunlight
Brown crispy leaf edges	Too much direct sun, dry air, or salt buildup	Sunlight, humidity
Sudden flower stalk, leaves turn bitter	Bolting from heat	Bolting guide
Sour smell from the pot, mushy stem base	Advanced root rot	Root rot guide
Fine webbing, sticky residue, tiny insects	Pests	Pest guide
White fuzz on the soil surface	Harmless saprophytic mold, usually overwatering	Houseplant mold guide
Plant just stopped growing, roots at drainage hole	Root-bound, needs repotting	Overcrowding

1. You’ve got drainage or water problems

Overwatering causes far more plant deaths than underwatering, and it is rarely about how much water you pour. It is about where the water goes afterward.

Roots need air as much as they need water. In saturated soil, the air pockets fill and the roots suffocate, rot, and stop taking up water at all. That is why an overwatered plant wilts: the roots are gone, so the leaves get nothing even though the pot is full of water.

Use a pot with drainage holes. No exceptions. Plenty of advice suggests putting gravel in the bottom of a pot with no holes; it does not work. It raises the saturated zone rather than removing it, and the plant still drowns, just more slowly.

If you are set on a container without holes, drill some. An electric drill and a masonry bit of ¼ inch or smaller will get through most ceramic if you go slowly, and use a bit matched to the material. Put a saucer underneath, and empty it after watering.

Water on the finger test, not a schedule. Press two inches into the soil. Dry means water. Damp means wait. Lifting the pot works too: a freshly watered pot is noticeably heavy, and a dry one is light. Learn the difference by feel once and you will not need the finger test often.

Watch your water quality. Most tap water is fine. Heavily chlorinated water is better left to stand overnight in an open can. Water from a water softener should never go on plants, because the sodium it exchanges for calcium accumulates in the soil and will kill the plant over a few months. Use rainwater or distilled water instead.

If the soil is saturated and smells sour or like rotten eggs, the roots are already rotting. Our root rot guide covers whether it can be saved.

2. Too much or not enough sunlight

Underlighting is the second great killer, and its symptoms are specific: stems stretch, the gaps between leaf pairs get longer, new leaves come in pale and small, and the whole plant leans hard toward the window.

Mediterranean herbs (rosemary, lavender, oregano, thyme, sage) want six to eight hours of direct sun. A south-facing window is the only orientation that reliably delivers it, and even that falls short between November and February in most of the US. A supplemental grow light closes the winter gap.

Too much sun is a real but much rarer problem, mostly in hot, dry climates. Cilantro, mint, chervil and parsley do better in an east or west window with indirect light, and scorch or bolt in a hot south-facing one. If your light is genuinely poor, grow the herbs that tolerate low light rather than fighting it.

Rotate pots a quarter turn every few days so growth stays even instead of leaning.

3. Not enough humidity

Central heating and air conditioning both strip moisture from indoor air, and it shows as brown, crispy leaf edges, worst in winter and worst near a heating vent.

This matters for the tropical and moisture-loving herbs (basil, lemongrass, mint, chervil), which prefer humidity around 50%.^[1] A pebble tray under the pot, filled with water to just below the tops of the stones, raises local humidity as it evaporates. A room humidifier does the same job better.

Do not do this for Mediterranean herbs. Rosemary, lavender, thyme, sage and oregano evolved in dry air and want 30–50%. Raising humidity around them encourages powdery mildew and makes root rot more likely. Move them away from the vent instead. Getting this backwards is a common way to finish off a struggling rosemary.

4. You’re using the wrong container

Size and material both matter.

Aim for at least 8 inches in diameter for most herbs. Roughly speaking, the root system occupies as much volume as the visible plant, and a pot that is too small dries out constantly and restricts growth.

Do not overcorrect. A pot much larger than the root ball holds a reservoir of wet soil the roots cannot reach, and that reservoir is where rot starts. Go up one size at a time.

Material changes watering frequency. Terracotta is porous and loses water through its walls, which suits rosemary, lavender and thyme and works against mint, basil and chervil. Glazed ceramic and plastic hold moisture longer. Our pot selection guide covers the tradeoffs.

5. Your soil mix isn’t right

Garden soil in a pot compacts, drains badly and often carries pests. Use a potting mix.

Beyond that, match the mix to the plant. Mediterranean herbs want something gritty and fast-draining, which usually means adding perlite or coarse sand to a standard mix. Moisture-lovers want the opposite, and extra coconut coir or peat moss improves water retention.

Our growing media guide covers the ratios and what each amendment actually does.

Potting mix also compacts over two or three years, and drainage gets worse exactly as the plant gets bigger. Repot into fresh mix periodically even if the pot size is still right.

6. Overcrowding is a killer

This bites hardest when starting from seed. A tray of seedlings looks healthy right up until they start competing, and then all of them do badly.

Thin ruthlessly. Pull the smaller, weaker seedlings and leave only the strongest one or two. It feels wasteful and it is the difference between one good plant and six poor ones. Chives are the exception; they grow as a clump and tolerate crowding.

An established plant that has outgrown its pot shows it by stalling: growth stops, water runs straight through, and roots appear at the drainage hole. Repot one size up in fresh mix. If the roots have formed a dense mat, tease them apart or trim the outer layer before repotting.

Crowding also cuts airflow between plants, which raises the risk of the fungal problems in our mold guide. Leave space between pots.

7. Your herbs need fertilizer

Potted plants exhaust their soil. Every watering leaches a little more nutrient out of the drainage hole, and after a few months there is not much left.

A monthly dose of dilute liquid fertilizer or a top dressing of compost through the growing season is enough for most herbs.^[2] Liquid seaweed is a gentle option, though it is a biostimulant rather than a feed and needs pairing with a nitrogen source.

Underdo it rather than overdo it. Excess fertilizer draws water out of the roots by osmosis and produces fertilizer burn, which shows as scorched leaf margins and a crust of salts on the soil surface.^[3] Herbs are also more aromatic when slightly underfed: rich soil produces big, bland leaves, which is why an overfed rosemary smells of very little.

Cut back sharply in winter when growth slows, and stop entirely for dormant plants. Our fertilizer guide covers types and timing.

8. You’re not harvesting right

Harvesting is not just taking food off the plant; done correctly it is what keeps the plant productive.

Wait until plants are at least six inches tall. Then pinch stems off just above a node, where a pair of leaves meets the stem. The plant responds by pushing out two stems where there was one, so every cut makes it bushier. Always work from the top.

Resist stripping the big lower leaves. They are tougher eating and the plant depends on them to photosynthesize, especially in low light. Our pruning guide covers the technique per herb.

Never take more than a third of the plant at once, and give it time to recover between harvests.

Some decline is not your fault. Basil, cilantro and dill are annuals: they grow, flower and die within a season no matter how well you treat them. When they start to fade, let them set seed or start a fresh pot. Our easiest herbs guide flags which of the common herbs are annuals and which will keep going for years.

When to give up on a plant

Some plants are worth saving and some are not.

A wilted plant on dry soil almost always recovers within hours of watering. A leggy, underlit plant recovers once you fix the light, though the stretched growth stays stretched and is worth cutting back.

A plant with a soft, blackened stem at soil level and a sour-smelling pot is usually finished. Root rot that has reached the crown does not reverse. Take healthy cuttings from the top if any remain, and start again.

There is no such thing as a green thumb. Every one of these failures is a condition you can change, and the plants that died taught you which condition it was.

References

1. Wolverton, B. C., & Wolverton, J. D. (2004). Interior plants: their influence on airborne microbes inside energy-efficient buildings. https://www.sciencedirect.com/science/article/pii/S0367253004700262 ↩︎

2. Effects of organic and inorganic fertilizers on container-grown plants. Communications in Soil Science and Plant Analysis. https://www.tandfonline.com/doi/abs/10.1081/CSS-200062434 ↩︎

3. Fertilizer burn and salt injury in turf and ornamentals. Michigan State University Turfgrass Information Center archive. http://archive.lib.msu.edu/tic/wetrt/article/1976nov14.pdf ↩︎