Your plants speak. No really! Though sometimes it might be a little difficult to understand what they are really trying to say, a lot of times they exhibit some symptoms when they are stressed. All you need to know to understand the sign language of your plants is to observe them closely. Plants exhibit their stress symptoms mostly on their leaves. Yellow leaves, wilted leaves, spindly growth, and a lot of other ways are how plants communicate with us.
Ready for some leaf lessons? Let's go!
Diagnosis: The first reason for wilting of plant leaves might be water stress. Wilting of leaves might be mostly due to underwatering or overwatering. Check the soil, if the top layers of soil felt dried when touched and the soil separates easily, then it is due to under-watering. If the soil feels damp and soggy and the basal leaves are mushy to the touch, then it is due to overwatering. Excessive heat and very dry air can also cause the leaves to be wilted.
Cure: Only water your plant when the top layers of soil feel dry to the touch, Maintain consistent moisture throughout the blooming period but do not make the soil soggy. Mist your plants, when the air feels too dry.
Diagnosis: The decaying of leaves is mostly due to excess moisture on the foliage. Never mist your plants, and do not make your foliage too wet while watering. Ensure that you mist your leaves in the morning instead of in the evenings so that the collected water in the crevices of the leaves has a chance to dry up before they catch fungal infections. On a general note, 50ml-80ml of water is enough to mist small to medium-sized plants while for larger and taller plants 100-150ml will suffice.
Cure: If your leaves are dusty, wipe them out with a wet cloth very gently once a week to remove the dust and improve transpiration. Along with the monitored watering, the mornings greatly help in keeping the foliage fresh.
Diagnosis: Yellowing of the leaves is mostly due to overwatering or nutrient deficiencies. Overwatering mushes the root leading the leaves to turn yellow. If the leaves are mushy or the soil is emitting a foul smell, then it is due to overwatering. If the older leaves are turning yellow, it is due to nitrogen deficiency, and/or the plant is going through its natural lifecycle and dying.
Cure: Yellowing can be controlled via monitored watering. For indoor plants 2-3 times a week is enough for the plant to grow well; for flowering and outdoor sun-loving varieties, always check the top soil dryness before watering. Use any well-balanced liquid fertilizers or nitrogen-rich fertilizers for soil or foliar application.
Diagnosis: If the entire leaf turns yellow and the veins remain green, it is due to interveinal chlorosis. Interveinal chlorosis is due to iron deficiency.
Cure: Just apply iron-rich fertilizers in the form of foliar spray.
DRY CRISPY LEAVES
Diagnosis: Leaf drying is almost due to under-watering. Unless the season is extremely cold and the soil is not drying, try not to skip watering for longer than 4-7 days for indoor plants (except once a week watering varieties like Monstera, Palms, etc) and 2-4 days for the flowering and sun sustaining varieties.
Too dry soil repels water leading to a drier root ball and eventually the plant drying and withering off.
Cure: Always check the topsoil when you water your plants and make sure that the excess water is draining out of the drainage holes at the bottom of the pot.
Diagnosis: The misshapen leaves are mostly due to biotic stress by pests. Aphids or thrips mostly cause abnormal sharpened leaves or disfigured leaves.
Cure: Use neem oil mostly @5ml per liter of water with some amount of liquid soap. You can also use insecticidal soap.
HOLES ON YOUR LEAVES
Diagnosis: Holes on leaves indicate the infestation by pests. Check the lower side of your leaves and folds of your leaves for larvae.
Cure: Use neem oil or Any insecticidal soap as a control measure.
POWDER MARKS ON LEAVES
Diagnosis: Powdery mildew is mainly caused by the fungus Podosphaera xanthii. If you are observing some powdery masses or marks on your leaves, then it might be due to mildew.
Cure: Use sulphur based fungicides at lower concentrations.
Diagnosis: Leaf spots might be due to fungus or bacteria. There is a very easy way to detect if your plant's leaves are infected by bacterial or fungal agents. Most of the bacterial leaf spots appear water-soaked and mostly angular whereas fungal leaf spots appear tan and yellow coloured and usually have concentric rings. There can be considerable browning as well around the infected parts.
Cure: Isolate the plant and remove debris and infected parts immediately and discard them. Sanitize all your gardening tools post using them for the trimming of the infected leaves. Use fungicides at lower concentrations to break the infection streak.