The set of evils they suffer can be classified into two categories:
- vegetation accidents due to lack of light, excess or lack of water, excessive heat, inappropriate exposure, etc. In some cases, there is no cure. For example, if you have tried several times to acclimatize ficus at home and all attempts have failed, the wisest is to choose another species of plant.
- enemies that attack houseplants as well as plants grown in the garden: animals (mostly insects) and diseases (especially mushrooms). There is usually a cure, but you have to first detect the enemy.
Identifying the harm that a plant is suffering from is not always easy. Here, from the main visible symptoms, is the probable enemy and the remedy when it exists.
Foliage becoming very pale green
Lack of light or fertilizer. The cure is simple. Put the plant in a better lit place or give it some natural fertilizer. Sometimes she needs both.
Yellowing of foliage
It reaches only one or two leaves of the base, which then fall, the remainder of the plant remaining in perfect health and showing a good vigor, in particular by giving young shoots, the harm is without gravity. It is likewise normal vegetation in some plants. On the other hand, when all the foliage turns yellow, it is a chlorosis due to the use of soil or limestone, a deficiency in food, or an excess of water that has caused root rot.
The veins of the leaves remain green and yellowing is more accentuated at the edge of the leaves. Try to revitalize the plant using an anti-chlorosis, but the remedy is to change the soil and water with rainwater. If it is root rot, healing is difficult. Try to save the plant by depositing it, cutting the damaged roots and relocating to a new earth. Above all, do a good drainage of the pot.
Brown spots on the foliage (often at the end of leaves and around)
Difficult acclimatization of the plant, abrupt growth in the vegetation, excess of water or fertilizer, washing of the leaves while exposed to the sun, cold air flow following the opening of a window . The remedy comes from the cause. But still it is necessary to succeed in finding it with exactitude. Almost always, there is no alternative but to cut the damaged leaves and, if the disease starts again, to change the plant.
Falling leaves from the base
Frequent accident among ficus, cordylines, crotons, etc., which is accentuated byr bad watering, irregular feeding or too dry atmosphere. Virtually unavoidable for some plants. Fighting causes including wetting.
Slow or no growth: almost always a lack of food. A plant with all appearances of good health must grow more or less regularly, observing periods of resting vegetation. Do not overdo, however, fertilizer inputs that may cause accidents.
Gnawed leaves
Caterpillars of various butterflies. Just pick them up by hand.
Greyish leaves
This dirty hue is caused by the bites of tiny mites, called red spiders. The plants are exhausted. Struggle with an acaricide specialty. The water sprays on the foliage slow down the proliferation of these fearsome enemies of house plants that are particularly prevalent in a dry atmosphere.
Floppy foliage, withered
Shortage of water, direct sunburn on the plant, especially through a window, intoxication by emanation of gas or various fumes, including tobacco. If it is not too damaged, the plant quickly regains its primitive appearance but, very often, its foliage dries out in places.
Discolored leaves with silvery spots
Attacks of thrips, a small insect barely visible to the naked eye. His bites exhaust the plants. Fight with a natural insecticide.
White felting on leaves and young shoots
Mushroom called powdery mildew or white. Treat preventively with a natural fungicide.
Red or brown spots on the leaves
They are small (2 to 5 mm in diameter) and generally numerous. It is about rust, a cryptogamic disease which is especially evident in winter on plants stored in a cool room. Geraniums are often affected. Treat preventively with a fungicide specialty and increase the aeration of the plants.
Black or greyish spots on the leaves
They are of various sizes, sometimes exceeding 2 cm in diameter, and irregular in shape. These spots then dry out and make way for holes. These are various diseases caused by fungi. The remedy is the same as before.
Black deposit on the leaves
A fungus that develops on aphids, whiteflies and mealybugs. Destroy these insects.
Small insects on leaves and young shoots: aphids
They are mostly green. The leaves are deformed and curl. Fight with a natural insecticide.
Scales on the leaves and stems
Mealybugs, small insects covered with a waxy shell. They are often found on succulents. Fight with a natural insecticide.
Loose flaky clusters on stems and leaves
Cochineal cousins of the previous ones. Same cure.
Small white flies flying around plants
Whiteflies. They can be very numerous and favor by their droppings the formation of a black deposit on the leaves. Water sprays are often enough to eliminate them, otherwise fight them with a natural insecticide.
With regard to most insects attacking houseplants, they have one thing in common: they do not like humidity. Frequent spraying of water on the foliage of plants hinders their implantation.
