What's Wrong With My Plant? How to Fix 12 Common Houseplant Problems

It's hard to know what’s wrong with your houseplant when it can’t open its plant mouth and tell you. While some plants may need a more in-depth assessment, most common houseplant problems can be fairly easily diagnosed.

You can determine the scope of the houseplant problem by doing some observation: what looks different or unusual about the plant compared to how it looked previously? Put your fingers in the soil to see how dry or moist it feels. Also, assess your plant's environment for seasonal or other changes: Is it near a cold, drafty window or a heating vent?

To help you figure out what’s wrong with your houseplant, we’ve broken down the most common houseplant problems and their fixes below.

Curling Leaves

Curling leaves houseplant leaves can be due to overwatering or heat stress. When overwatering is the cause, the leaves will curl and turn yellow, then likely turn brown and drop off.

Compacted soil that can't absorb water effectively may also cause leaves to curl.

The Solution

The easiest way to address overwatering is to allow the top inch of the soil to get completely dry in between waterings. Also be sure the container has sufficient drainage.

To prevent heat stress, make sure the plant is not too close to a heating element, or provide cooling air during hot weather. Some plants may need to be moved out of direct light.

Yellowing Leaves

If your plant's older leaves are turning yellow, this is either because the plant is dropping its older leaves to redirect its energy to new leaves (a normal process) or root rot. It can also be due to nitrogen deficiency, which can also cause the older yellow leaves to drop.

If all of the leaves are turning yellow, this is more likely due to a potassium deficiency.

The Solution

If your watering habits are fine, you can try a nitrogen or potassium fertilizer and see if that fixes it.

Brown Leaf Tips

If the tips of leaves are brown and crispy looking, this may mean a potassium deficiency in your soil. For some plants it can also be underwatering.

Brown leaf tips may also be caused by thrips, a tiny pest that can eventually cause leaves to curl and turn crispy. These are visible to the naked eye and look like tiny white threads,

The Solution

Add potassium to the soil with an amendment. Reassess your watering habits. For suspected thrips, use a neem oil spray on the affected leaves.

Wilting or Droopy Leaves

Wilting, droopy leaves are often a sign of underwatering or overwatering. Feel the soil; if it it’s dry, it’s underwatered. If it’s wet to the touch, it's waterlogged.

Wilting leaves can also be caused by the plant receiving insufficient light, which can affect the plant's ability to produce nutrients.

The Solution

Reassess your watering habits. Check soil moisture level more often. Avoid watering unless the top inch or two of the soil is dry to the touch. Also make sure the plant's container has good drainage, and consider repotting your plant if necessary.

Try relocating your plant to a better position where it gets better exposure to sunlight. Do this gradually, giving it a little more sun exposure each day.

Sticky Leaves

if your plant's leaves seem to have a sticky to the touch, it is most likely be due to insects. Aphids are a common cause, as they secrete a sticky sap residue known as honeydew. It may also be mites, or scale, which drop a sticky residue onto the lower leaves of the plant.

The Solution

Spray down your plant with a removable showerhead to wash away pests, then use an insecticidal soap or neem oil on the leaves. to remove the sticky film. You can also use basic dishwashing liquid to make a diluted spray solution to apply to the leaves.

Wrinkled Leaves

Wrinkled leaves are tricky to diagnose, as the cause may be underwatering, low humidity, or a combination of factors. The best treatment is to address each potential problem separately, starting with watering, which is the most common cause of wrinkled leaves.

For plants whose leaves are a little thicker (snake plant, Hoya, succulents) a wrinkled leaf is often an indication of underwatering.

The Solution

First make sure the plant is receiving adequate water by checking the soil's moisture more frequently and adjusting your watering. Get a moisture meter if you don’t trust your own judgment. 

Lack of humidity may be an issue for some plants also, especially in winter when heat makes the air dry. You can use a humidifier, or make a pebble tray to create a more humid microclimate.

Brown Spots on Leaves

If you have a plant that has very particular watering needs, such as a calathea or fiddle leaf fig, inconsistent or incorrect watering can cause brown spots on leaves.

But with plants without particular watering needs, brown spots or patches on leaves are nearly always due to a mineral deficiency. But whether it is due to a lack of nitrogen, phosphorous, or potassium may be difficult to figure out. 

The Solution

For a plant with particular watering needs, check the soil more often to be sure the moisture level is correct.

If you want to try fertilizer for this solution, find one with an NPK ratio suited to houseplants. Usually a balanced 10-10-10 liquid solution is recommended (10% of each mineral). A 3-1-2 ratio is good for tropical houseplants, though that assumes it is a nitrogen deficiency.

Faded Leaves

Faded leaves on a houseplant are usually a result of insufficient lighting, or too much lighting, in which case they might also get leaf scorch (pictured above). This is especially apparent on leaves with variegation.

The Solution

Consider your plant's current lighting condition and adjust. If it's in low light, try to give it 2 to 3 more hours of light per day in a sunnier window and see if there's an improvement. If it's in high light, move it into lower lighting.

If you don't have a brighter location for your plant, try adding grow lights.

Mold or Mildew on Leaves

Mold or mildew on your plants is unsightly and often a sign of bacterial disease. Sometimes the cause is as simple as too much humidity or moisture. 

Powdery mildew is the most common cause of a moldy appearance. It’s caused by a fungus that leaves a pale grey or white residue on the tops and/or bottoms of leaves.

The Solution

If there is also mold on your soil, this indicates an overabundance of moisture, one which may also cause root rot. Repot your plant in fresh soil in a container with good drainage.

To treat powdery mildew on leaves, you need an an anti-fungal treatment. You can also make your own anti-fungal spray easily at home.

Chewed-Up Leaves

If your indoor plants have leaves that look ragged and chewed, you may have insect pests, such as spider mites or mealybugs. (It’s also possible your pets might be biting them.)

The Solution

First, trim off the damaged leaves. If insects such as spider mites, aphids, or mealybugs are present, rinsing them off with a strong spray from a handheld showerhead is a good first solution. For tougher pests, use a basic insecticidal soap spray. Keep an eye on the plant for a few weeks to repeat treatment as needed.

If you have pets such as dogs or cats, keep your houseplants where they can't reach them (especially if the plant is toxic).

Misshapen Leaves

Leaves that are small or oddly shaped may be caused by various things, but primarily nutrient deficiency or pests, especially on young leaves. Small leaves can sometimes be caused by the plant being pot-bound.

The Solution

If the new growth on your plant appears stunted or misshapen, the cause is probably insect pests such as spider mites, thrips, or aphids. Use an insecticidal soup spray to eliminate them and prevent them from invading your plants.

If there are no pests present, check to see if your plant is ready for a bigger pot size.

Curling and Yellow Leaves

If leaf color is fading to yellow and the leaves are curling a bit, this is likely due to a nitrogen deficiency, but it could also be overfertilizing. Look to see which leaves are doing it—the first leaves affected will be older leaves if the problem is nitrogen deficiency.

With nitrogen deficiency, the leaves sometimes can look wrinkled instead of curling.

The Solution

Consider your fertilizing habits and respond according to whichever seems more likely.

Read the original article on The Spruce.