60-second triage
What’s actually wrong with it?
One question at a time, honest answers, no plant-forum lore. Most people land on a likely culprit in two taps — and it’s free either way.
First, thirty seconds of hands-on
Do all four before you answer anything. They cost half a minute and they knock out most of the possibilities.
- Stick a finger in the soil. Second knuckle deep, not the surface. The surface is always dry. Wet, damp or dry down there?
- Pick the pot up. Heavy for its size means the mix is full of water. Suspiciously light means bone dry.
- Look at the bottom of the pot. Is there a drainage hole? Is it standing in a saucer or a cachepot with water in it? Roots poking out?
- Turn a leaf over. Phone torch on the undersides and the joints where leaf meets stem. That is where every pest lives.
Don’t fancy the quiz? Browse every answer, just ask us, or — if it is past all that — call the coroner.
Question 1 of 2
Most likely
Overwatering
Soil that is still wet when you next go to water means the roots cannot get oxygen. The plant sheds its oldest leaves first, because those are the cheapest ones to lose.
Do this today
- Do not water it. Wait until the top two inches are dry to your knuckle. In a dim room that can easily be ten to fourteen days.
- Tip out any standing water. Lift the nursery pot out of its cover or saucer and pour away whatever collected underneath.
- Do not feed it. A soggy root system cannot use fertiliser, and salts build up in wet soil.
Also worth reading: Three reliable ways to tell when a plant actually wants water
Most likely
Root rot — and this one is urgent
Mushy, sour-smelling, and spreading for as long as it sits in wet mix. This is the one situation in the whole guide where an emergency repot is the right move.
Do this today
- Unpot it now and rinse the roots under the tap so you can actually see what you are dealing with.
- Cut back to firm, pale tissue with clean scissors. Anything brown, soft or stringy has to go.
- Repot into fresh, gritty mix in a pot with a drainage hole, and keep it barely damp for a couple of weeks.
Most likely
Underwatering
Limp but dry and papery, and the pot feels light. Nothing is broken here — it simply ran out. A plant in this state usually perks up within hours, sometimes dramatically.
Do this today
- Water thoroughly, until it runs out of the drainage holes. A splash on the surface never reaches the roots.
- If the mix has shrunk from the sides, stand the whole pot in a few inches of water for twenty minutes so it rewets evenly.
- Then check by finger, not by calendar. Same plant, same pot, different week, different answer.
Also worth reading: How to tell when the mix is dry all the way down
Most likely
Transplant or move shock
Repotting tears root hairs, and a move changes the light overnight. Either one costs the plant a few weeks, and it pays for them with its oldest leaves.
Do this today
- Leave it exactly where it is. Another move restarts the clock.
- Water less, not more. Damaged roots cannot drink at the old rate, so the old rate now drowns them.
- Do not feed it until you can see new growth.
Most likely
Not enough light
It is alive, it just is not earning enough to grow. Long bare stems, small pale new leaves and fading variegation are all the same sentence.
Do this today
- Move it closer to the window. The light a metre back from the glass is a fraction of what is at the sill, even though your eyes say otherwise.
- Give it a quarter-turn each week so it stops leaning and fills out evenly.
- Do not feed it to compensate. Light is the missing ingredient, not food.
Also worth reading: The same problem, seen from the flowering end
Most likely
Seedlings stretching for light
Tall, thin and falling over is a light problem, not a feeding problem. A spring windowsill is far darker than it looks to you.
Do this today
- Get them brighter, today. As close to the glass as you can, or a few inches under a light.
- Give them a breeze. A fan on low, or a daily brush of your hand across the tops, thickens the stems.
- Do not feed them. Rich food on a stretched seedling just makes it floppier.
Most likely
Enough light to live, not quite enough to bloom
Healthy leaves and no flowers is nearly always the light. Blooming costs a plant far more than surviving does, so it is the first thing dropped.
Do this today
- Move it to the brightest spot that does not get direct midday sun on the leaves.
- Give it a month before you judge. Buds are set well before you can see them.
- Do not reach for a bloom booster first. If you do feed, follow the official feeding chart rather than a number you half remember.
Most likely
Dry air
Brown confined to the very tip, which is the furthest point from the roots. The edge is running out of water faster than the plant can resupply it.
Do this today
- Group plants together, and add a small humidifier if you have one. Those two do the work. A pebble tray is harmless but does little for the canopy, and misting looks caring while evaporating within minutes.
- Move it away from any heat vent or radiator.
- Even out the watering. Consistently barely damp beats a swing between soaked and bone dry.
Most likely
Tap-water minerals
Spider plants, dracaenas, calatheas, prayer plants and cordylines are the fluoride-and-salt sensitive crowd. They brown at the tips while everything else in the room is fine.
Do this today
- Flush the pot. Run water slowly through the mix at the sink for a minute or two and let it drain freely, so salts leave rather than concentrate.
- Switch to filtered, distilled or rainwater. Standing the water overnight is the advice everyone repeats and it does not help here — it lets some chlorine off, and leaves the fluoride, the chloramine and the salts exactly where they were.
- Trim the dead tips following the leaf’s own shape, so the cut does not shout.
Most likely
Fertiliser burn
Crispy tips plus a white crust on the soil or the pot rim means salts have built up faster than the plant can use them. The roots are being burnt from the outside in.
Do this today
- Stop feeding, completely, for now.
- Flush the pot at the sink — several pot-volumes of water, draining freely each time, to carry the salt out.
- When you start again, follow the official feeding chart rather than a remembered number. Dose matters more than brand.
We haven’t written this one up yet. Ask and it goes to the front of the queue.
Most likely
Sunburn
Bleached, sharply defined patches on the side facing the glass, after a move somewhere brighter. Leaves cannot tan — the damage on that leaf is permanent.
Do this today
- Move it back out of direct sun, or diffuse the light with a sheer curtain.
- Leave the damaged leaves on. They look terrible and they are still working.
- Next time, move a plant brighter over a week or two, not in one afternoon.
We haven’t written this one up yet. Ask and it goes to the front of the queue.
Most likely
Heat stress, or harmless leaf roll
Green leaves curling inward like a taco in a hot spot is the plant reducing the surface it loses water from. It is a coping mechanism, not a disease.
Do this today
- Check the soil first. Bone dry means this is thirst, not heat.
- Get it out of direct afternoon sun and away from hot glass.
- Water deeply and consistently instead of little and often.
Most likely
Too much water, showing up mid-leaf
Where the spot sits tells you which problem you have. Soft-edged dark patches in the middle of the leaf, with wet soil underneath, is a water story rather than a disease.
Do this today
- Check at knuckle depth before you water again. Damp means wait.
- Empty the cachepot or saucer after every drink.
- Leave spotted leaves alone unless they have gone fully brown.
Most likely
Fungus gnats
They breed in damp surface soil, which is why swatting the adults changes nothing at all. Dry the top of the mix and the cycle stops.
Do this today
- Let the top inch or two dry out properly between waterings. That is the actual fix.
- Water from the bottom for a few weeks so the surface never gets damp.
- Yellow sticky traps for the adults while the larvae die out.
Most likely
Spider mites
Fine webbing in the joints, gritty undersides, pale stippling on top. They love hot, dry, still air, which describes most centrally heated rooms in winter.
Do this today
- Isolate it today — a different room, not the other end of the shelf. Mites travel on contact and on air currents.
- Rinse the whole plant, undersides especially, in the shower or at the sink.
- Check again every week. One rinse never gets them all, and the eggs are still there.
We haven’t written this one up yet. Ask and it goes to the front of the queue.
Most likely
Mealybugs
White fluff in the leaf joints, and something sticky on the leaves or the surface below. The fluff is a waxy coat, which is why a plain spray runs straight off them.
Do this today
- Isolate the plant.
- Touch each one with a cotton bud dipped in rubbing alcohol. It dissolves the wax, which nothing else does.
- Re-check every few days for a month. They hide in the crown and under the pot rim.
We haven’t written this one up yet. Ask and it goes to the front of the queue.
Most likely
Scale
Small brown bumps that scrape off with a fingernail, shiny sticky leaves, and sometimes black sooty patches sitting on top of the stickiness.
Do this today
- Isolate it, then scrape or rub the bumps off with a soft cloth.
- Wipe the sticky residue off every leaf, so you can see new arrivals against a clean surface.
- Re-check weekly. The crawler stage is nearly invisible.
We haven’t written this one up yet. Ask and it goes to the front of the queue.
Most likely
White mould on the soil
Harmless in itself — a fungus feeding on decaying matter in the mix. What it is telling you is that the surface never dries and the air is not moving.
Do this today
- Scrape the fuzz off and let the top of the mix dry out properly.
- Improve the airflow. More space between pots, or a fan on low in the room.
- Watch for fungus gnats. Same conditions, considerably more annoying.
Also worth reading: If the flies have already turned up
Most likely
Rootbound
Water running straight through in two seconds, a pot that dries out in a day, roots out of the drainage holes. There is more root than soil in there.
Do this today
- Repot one size up. Not three — a pot that is too big holds water where there are no roots to drink it.
- Tease the outer roots loose so they grow outward instead of continuing round in a circle.
- Water it in well, then leave it alone for a few weeks.
We haven’t written this one up yet. Ask and it goes to the front of the queue.
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