Man growing plants in vials.

Types of Physiological Problems of Plants

The conditions in which the plant is growing will have a direct bearing on its health. Any deficiencies will cause the plant to show symptoms, although on occasion, these may be similar to those caused by disease. Use a process of elimination to identify the cause of the problem.


Cold air from a door or win­dow lowers the temperature and humidity around the plant. Growth slows and hardens. Tender plants may not survive.

Remedy: Move the plant to a position further into the room with a constant temperature.

Erratic watering

Plants need water on a constant basis, and giving copious quantities, followed by none at all for days on end will result in poor growth and flowering, and the shedding of flower buds.

Remedy: Check the needs of the indi­vidual plant and water regularly. Fluctuating temperatures (See Drafts)

Incorrect humidity

The amount of moisture in the air affects how much water is lost ty the plant. If the air is drier than the plant likes, the leaves will turn dry or develop brown edges. If the air is too moist, the plant may fall victim to fungal attack.

Remedy: Check the cultural condi­tions for the plant.


In areas where the tap water is “hard” (contains a lot of cal­cium), any which drips on the leaves during watering will dry to leave a white, powdery deposit.

Remedy: Using rainwater and always watering into the saucer should help.

Low light

Low levels of light will cause growth to become elongated, pale, and soft. The plant is unable to support its own weight. Variegated plants will become all-green as the plant compensates for the lack of chlorophyll in the yellow/white part of the leaf.

Remedy: Move the plant to a position with more light.

Nutrient deficiency

Depending on which mineral(s) is missing, the growth can be stunted, yellowed, purple, mottled, or distorted, with an absence of flowers or fruit, or a susceptibility to disease.

Remedy: Apply a balanced fertilizer. Overfeeding Particularly with nitro gen, this gives a tall, soft, floppy plant, with plenty of leaves but no flowers

Remedy: Give water, but do not feet: for several weeks, then adopt a regular feeding regimen, according to the pack.


Variegated plants occasionally produce a plain green shoot which will assume dominance over the others if it is left in place due to its extra vigor (it contains more chlorophyll).

Remedy: Cut out any all-green shoots as close to their base as possible.


Hot sun on leaves causes overheating and cell damage. If droplets of water are left on the leaves, the effect is magnified.

Remedy: Plants with sappy leaves need keeping out of direct sunlight. Those with hairy leaves (which trap water) need watering from below.

Too much water

The more water in the soil mix, the less room there is for air. Without air, the roots will die and rot.

Remedy: Slant the pot at an angle to allow the excess water to drain away.

Too little water

Without enough water, the roots will shrivel up and die. The plant needs water to trans port nutrients and if this cannot take place, the plant wall die. If the plant has become too dry, it will never be able to recover.

Remedy: Submerge the root ball in water until bubbles stop rising to the surface.


Growth is slow’ and hard, and there are few flowers. The stems may have a purple tint.

Remedy: Begin a regular feeding regimen, according to the pack.

Winter dormancy

Many plants need a period of dormancy between growing seasons, and this often coincides with winter, when light levels and temperatures are at their lowest. Growth slows right down or stops.

Remedy: Leave the plant alone until it. shows signs of growth again, then begin to apply fertilizer and water. Within three weeks, it will be back in full growth.