Why Are My Houseplant Leaves Turning Yellow? 7 Causes and Fixes

Houseplant leaves turning yellow tell you something is off, but not what. The same faded color can come from soggy roots, bone-dry soil, a dim corner, a hungry plant, tiny pests, a cold draft, or plain old age. So before you change anything, slow down and look at the evidence: which leaves are yellow, how the soil feels, and what the roots look like.

Read the pattern before you treat anything

Where the yellow shows up is your best clue. Treat this table as a starting point; causes overlap, and a plant can have two problems at once.

What you see	Likely cause	First move
Lower and inner leaves yellow or wilt, soil stays wet	Overwatering	Check the roots, let the soil dry
Lower leaves yellow after long dry spells, soil pulled from the pot edge	Underwatering	Rewater thoroughly
Pale, stretched growth in a dim spot	Too little light	Move closer to a window
Oldest leaves yellow and brown, plant crowded in its pot	Nutrient shortage	Repot or feed lightly
Speckled, yellowed or misshapen leaves	Pests	Inspect leaf undersides
Yellowing or leaf drop soon after a move or a cold snap	Stress from change	Stabilize and wait
One lower leaf at a time on a mature plant	Normal aging	Nothing

The 7 causes, and what to do about each

1. Too much water

In its houseplant diseases and disorders factsheet, Clemson explains that overwatering cuts the oxygen available to roots and favors root disease. The University of Maryland Extension describes the main symptom in its page on overwatered indoor plants as wilting or yellowing of the lower and inner leaves, and notes that an overwatered plant can look just like a thirsty one, because damaged roots can no longer take up water.

That is why the roots matter more than the leaves. Tip the plant out and look:

White roots are generally healthy, according to Illinois Extension.
Dark brown to black roots point to overwatering.
Rusty orange to light brown roots point to underwatering.

If only a few roots are brown and soft, Clemson advises cutting them out and repotting in sterile soil. If most of the root system is dark, soft and dead, Clemson's blunt advice is that discarding the plant is the better option.

Going forward, make sure the pot has a drainage hole and empty the saucer after watering. Our guide on how to tell when a houseplant needs water covers the routine.

2. Too little water

Clemson notes that lower leaves can also yellow when a plant is left too dry for an extended time, and that chronic underwatering leads to wilting, leaf curling and eventually death. The giveaway is a light pot and dry mix, sometimes with a gap at the pot wall.

Maryland's advice for that gap is to water several times so the mix rehydrates instead of letting water run straight down the sides. After that, water thoroughly each time, until it comes out of the bottom of the pot.

3. Not enough light

Too little light is on Clemson's short list of yellowing causes, and the Royal Horticultural Society lists a position that is too shady among the reasons for leaf damage on houseplants. Its remedy is simple: move the plant somewhere brighter, such as a south-facing windowsill in winter.

The RHS also notes that too much midday sun can cause drooping or yellow scorch. See how to read your windows before you relocate anything.

4. A hungry or pot-bound plant

When the lowest leaves yellow and brown while the rest of the plant looks fine, Clemson says the cause is generally a nitrogen or iron deficiency, and that pot-bound plants are especially prone to it. Regular fertilizing and repotting in fresh soil prevent it.

Resist the urge to pour on fertilizer as a first response, though. Illinois Extension points out that a root-bound plant may need a larger container instead. And Iowa State University Extension warns that salt from excess fertilizer can damage roots; it recommends using fertilizer at half or quarter strength indoors and not with every watering. A white or gray crust on the soil or pot rim is a sign of salt buildup, per Clemson. Flushing the soil with clear water until it drains out the bottom helps.

5. Pests

Turn a few leaves over. Clemson's factsheet on common houseplant insects and related pests says aphids suck plant sap and leave yellowing, misshapen leaves, while spider mites cause light speckling and, left unchecked, bronzed or yellowed foliage. A silky web usually means a heavier mite infestation.

Start gently: Clemson recommends repeated forceful sprays of water for spider mites and notes that washing smooth-leaved plants every two to three weeks discourages infestations. Keep new plants apart from the rest for six weeks so hitchhikers show themselves.

6. A move, a draft, or a chill

Illinois Extension explains that many plants go through an adjustment period whenever they are moved, which can show up as yellowing or leaf drop. Clemson puts a rough number on it: leaf drop after a major environmental change should last only about three weeks.

The RHS adds cold, a sudden drop in temperature, and drafts to the list of yellowing triggers. Check for a leaky window, an exterior door or a vent nearby. If the yellowing continues for more than a few weeks, Illinois Extension suggests trying another spot and adjusting watering slightly.

7. Ordinary aging

Sometimes nothing is wrong. The RHS states that it is normal for the odd lower leaf on a mature plant to yellow and fall. If new growth looks healthy and you are losing one old leaf now and then, leave your routine alone.

A five-minute checkup

Run through this before you buy anything.

Push a finger into the soil. Wet, damp or dry?
Lift the pot. Heavy or light for its size?
Confirm there is a drainage hole and no water sitting in the saucer.
Slide the plant out and note the root color.
Look at leaf undersides for specks, webbing or insects.
Ask what changed lately: a new spot, colder nights, a different watering habit.

What not to do

Change one thing at a time. If you repot, fertilize and move a plant on the same day, you will not know what helped, and you pile new stress onto a weak plant. Illinois Extension is direct that fertilizer and household pesticides are not an appropriate first response to a struggling plant.

Give each fix time, too. Illinois frames recovery from overwatering in steps: hold off until the soil is quite dry, restart watering gradually, feed with a water-soluble houseplant fertilizer after two weeks, and repot in fresh soil only if the following two weeks bring no improvement.

Frequently asked questions

Overwatering or underwatering: how can I tell?

Check the soil and the roots, not the leaves, because both problems can cause yellowing and wilting. Wet soil with dark brown to black roots points to overwatering. Dry, shrunken mix with rusty orange to light brown roots points to underwatering.

Should I cut yellow leaves off?

You can, but treat it as tidying, not treatment. Removing a yellow leaf does nothing about the cause, so do the checkup first. As general practice, wait until the leaf is mostly yellow, then snip it off with clean scissors.

Will fertilizer fix yellow leaves?

Only if a nutrient shortage is the cause, which is most likely when the oldest leaves yellow on a plant that has been in the same pot for a long time. Otherwise feeding will not help, and excess fertilizer can add salt damage to the roots.