What's wrong with my leaves? Wilting, Drooping, Dropping, Yellowing and other Sad Leaf Problems
Leaves tell you a lot about the overall health of your plant. They are usually the first organ to show signs that something is amiss. Learn how to recognize plant ailments from common leaf problems with our guide.
This is a common and easily visible symptom. On it's own, discoloration (paling, yellowing, or browning) won't tell you much as it can signal a number of ailments. But does indicate the plant is in some kind of distress.
Yellowing mature leaves
Mature leaves tend to be the larger ones growing nearer to soil. Smaller leaves growing nearer to the tips of stems are younger.
When the edges of mature leaves start to yellow, you don't need to worry too much if this is not accompanied by other symptoms. The plant is naturally shedding older leaves as they age or you may simply need to water the plant.
Scot Nelson https://www.flickr.com/photos/scotnelson/37066938605
If younger leaves are going yellow - whether all over, in patches, or along the edges - something is wrong with your plant. Taken in isolation however, yellowing leaves won't allow you to pinpoint the underlying problem. This is a very general symptom that can indicate an array of ailments. You'll need to consider contextual factors and accompanying symptoms to find out what the plant needs.
Often, the cause of yellowing leaves might be as simple as under-watering. If the plant is a species that needs regular watering but you have left the soil bone-dry for a fortnight, it is reasonable to assume that is simply thirsty. If the plant needs partial shade and has been placed in a south-facing heat-trap, it is a no-brainer that the plant is parched.
If it is the growing season (spring and summer) and you have not been fertilizing, yellowing leaves - particularly on the edges - might signal a nutrient deficiency. This would not apply if the plant is a succulent or a cactus. These species tend to need little or no feeding.
You won't be able to tell from yellowing leaves alone which nutrient the plant is lacking. It is likely to be one of the three macronutrients - nutrients that plants need in greatest amounts: nitrogen, phosphorus, or potassium. Chances are it will be nitrogen. If you can't get a soil test kit, find out what kind of fertilizer the particular species requires and follow a regular feeding regime suited to the plant. Use liquid fertilizer for the soil and follow the manufacturer's instructions. Alternatively, you can get foliar fertilizer. You spray this directly onto the leaves. Foliar spray should fix the discoloration in a few weeks.
Unfortunately, yellowing can also indicate over-fertilization too. It'll all depend on whether how often you have been fertilizing your plant.
If you have given your yellowing plant fertilizer, proper lighting conditions, and water, you may have a pest problem. To identify the pest at large, read on for more symptoms.
Figure 7 (bottom center) shows an apple tree leaf burnt by excess nitrogen. Ottawa : Dept. of Agriculture, https://commons.wikimedia.org/wiki/File:Apple_nutrition_(1941)_(19124665773).jpg
Dark brown patches on the edges can indicate nutrient scorching. This happens when you've overfertilized your plant. Although all plants must absorb essential nutrients from the soil to survive and grow, only minuscule amounts are necessary. Since houseplants sit in a small volume of soil, it is very easy to over-feed them.
If dark brown patches on your leaf overlap with areas where it is receiving direct sunlight, this can indicate light scorching. Your plant is receiving too much sunlight and needs to be moved to a more shaded area.
Charles J. Sharp https://commons.wikimedia.org/wiki/File:Green_leafhopper_(Cicadella_viridis).jpg
Tiny white specks might indicate leafhoppers. This is especially the case if it is accompanied by yellowing leaves that then turn brown.
Leafhoppers are greenish blue or brownish grey insects up to 0.5 inches long. They usually piggyback on houseplants that have been brought indoors from being kept outside, so inspect your plants and pots thoroughly any time you re-locate them.
White spots and blotches
White blotches can be caused by dampness on the leaves. They are larger and more spaced out than the white specks caused by leafhoppers.
This symptom is common in African violet and other furry-leaved species that hate getting their foliage wet. Avoid getting any droplets on the leaves when you water these species. You can also water from the bottom by sitting the pot in a saucer full of water until the soil is completely soaked. Then, set the pot on a dry surface so that any excess can drip off.
If your plant is not one of those species that does not like water on its leaves, white spots may indicate a fungal problem. Remove all affected leaves and change the potting mixture. Treat the plant with a fungicidal spray suited for your plant.
Leaves losing shape or dropping
Scot Nelson https://www.flickr.com/photos/scotnelson/15187475169
Drooped leaves may have lost its turgidity (water tension in cells that holds the plant upright) but might otherwise appear healthy and green.
Like yellowing leaves, drooping can have many causes. It can simply indicate an under-watered or over-heated plant but not always. Under-watered plants wilt and brown, but drooping leaves do not necessarily look drier.
Apart from too much heat or too little watering, drooping can indicate inadequate humidity, inadequate light, or too much dust on the leaves. Read our full guide on drooping leaves here.
This is perhaps the easiest symptom to diagnose and fix. Wilting most likely indicates that you need to water your plant ASAP.
However, remember that wilting can also be caused by over-watering. You'll have to make a judgement based on whether you've been watering frequently or whether you've left the soil too dry.
This symptom appears in succulent plants with fleshy leaves. It indicates the same thing as wilting leaves - your plant needs watering.
Watching a plant lose its leaves is one of the saddest sights in gardening. Again, you need to look for accompanying symptoms in order to pinpoint the problem. Leaf drop can indicate too much or too little water, high fluctuations in temperature, well as nutrient deficiency or exposure to pollutants.
Foreign growth on leaves most likely indicates a pest or fungal problem.
Dmitry Brant https://commons.wikimedia.org/wiki/File:Powdery_mildew_9.jpg
These are fungal spores that spread through water or air currents. Fungal infections are common in high humidity spaces with low air circulation. Remove all affected parts and spray with neem oil.
Scot Nelson https://www.flickr.com/photos/scotnelson/12346592585
White fluff on the stems and leaves indicates mealy bug. The fluff is the insect's outer camouflage.
Wipe away the fluff completely with a sponge. Spray the plant with water and insecticidal soap, adding one teaspoon of the soap to 20 oz water. Then, wipe the plant down again with the sponge. Repeat every two to three days.
Brown or orange blobs on leaf undersides and sooty mold
Katja Schulz https://www.flickr.com/photos/treegrow/46980983712
These blobs are the sticky secretions of scale insects. The insects themselves are small, flattened and white, yellow, or brown in color. If there are only a few, pick them off by hand or using a toothbrush.
Spraying with neem oil may work but scale insects are more problematic to remove since they have a hard protective shell. If you want to treat a large outbreak, you cay order a batch of live Steinernema feltiae that will eat the pest.
If you find a dark sooty substance on just the underside of your fern leaves, this does not necessarily indicate an infestation. They are more likely to be the fern's reproductive spores.