Submitted by jean-paul on Thu, 05/03/2012 - 12:34
Brown or yellow leavesOccasional yellowing of lower leaves is natural. Temperature extremes, chills and drafts, overfeeding, low humidity, not enough fresh air, overwatering, underwatering, underfeeding.
Yellow or white ring and spots on leavesSplashing cold water on foliage while watering plants.
Leaf dropUsually a sudden change in environment; especially temperature or light intensity, cold water, dry air, transplant shock, overwatering, overfeeding.
Bud dropToo hot or cold during their development, shock from moving from greenhouse to home, poor humidity, draft shock.
Slow growthDuring winter, probably due to poor light or natural dormancy. Otherwise, usually overwatering or underfeeding. Can also be sour, undrained soil, cramped or dry roots.
Loss of foliage color, pale weak growthOverwatering, lack of fertilizer, insufficient light, high heat.
Yellow or brown spotted leavesOverwatering, sun scorch from direct sunlight, drought, water left on leaves in hot sun, insects, damage from insecticides.
Dry crumbly leavesHigh heat, low humidity, overfertilizing, insecticide damage.
Wilted leaves, new growth smallOvercrowded roots.
Abnormally long stems, leaves long and paleInsufficient light.
Leaves curl under, new leaves are small and compactToo much light, on occasion chilling.
Collapse of plantExtreme heat or cold, gas fumes, poor drainage causing root rot, sudden change in environmental conditions. Bacteria or virus disease is a possibility, but highly unlikely, particularly if soil is sterilized before use.
Mushy, dark stems, rottingToo much water particularly in cold weather, poor drainage, poor ventilation, fungal attack encouraged by damp, cold conditions.
Swelling on leaves and corky ridges, water soaked spots that turn red or brownOedema: plant has absorbed too much moisture because of warm moist soil and cool moist air. To stop this, raise heat, lower humidity and place pot where soil will not heat.
Tips of leaves turn brownPoor humidity, potash deficiency, underwatering.
Plants bear few flowers and excess foliageToo much nitrogen supplied.
Lower leaves turn yellow and remain on plant. New leaves are small. Stunted stem.Lack of fertilizer, particularly nitrogen.
White crust on soilBuild up of fertilizer salts, cured by leaching with water and removal of crust.
WiltingNot enough water, too much heat or light. If these are not to blame, there may be root damage caused by overwatering, pests or overfertilizing.
Yellowing between the veins of young leaves, older leaves are less severely affected.Iron or magnesium deficiency.