The following table is provided to assist growers and others in diagnosing a few problems which develop in the culture of tropical foliage plants.

* General chlorosis of all leavesInsufficient fertilizer, very bright light, high temperature.
* General chlorosis of youngest leavesLack of iron or manganese, plants held in dark for too long period; agricultural chemicals.
* General chlorosis of older leavesLack of nitrogen or potassium, high soluble salts, poor soil aeration.
* Leaf edges chlorotic Lack of magnesium and potassium (lower leaves), high soluble salts, spider mite feeding, agricultural chemicals.
Areas between veins chloroticLack of iron or manganese, spider mite feeding, sulfur dioxide pollution, agricultural chemicals.
Chlorotic spots (round)Bacterial or fungal disease, agricultural chemicals.
Chlorotic spot (irregular)Cold water, bacterial or fungal disease, virus or virus-like disease, agricultural chemicals.
Stippled or dot-like chlorosisSpider mites, planthoppers, leafhoppers or thrips.
Mosaic-like chlorosisCold water, virus or virus-like disease, agricultural chemicals.
Water soaked or greasy coloured spotsExcessively high temperature, low air temperature, cold water contacting foliage, bacterial or fungal disease, foliar nematodes, agricultural chemicals.
Edge of leaf or tip of leaf deadPotassium deficiency, excessive boron, high soluble salts, fluoride toxicity, high temperature, low temperature, plant became too dry, spider mites, bacterial disease, agricultural chemicals.
Spots or sectors of leaf blade deadCold water, leaf miner feeding, bacterial or fungal disease, foliar nematodes, agricultural chemicals.
Dead areas on both edge and internal portion of leaf Excessive intensity, low air temperature, colored water, foliar disease, feeding from a number of pests, air pollution, agricultural chemicals.

Additional Note from D.P.I.

* Before checking on insufficiency, firstly examine the tree for root rot, collar rot and mechanical damage (of lawnmowers, whipper snippers etc.)

R. W. Henley,
Foliage News, Volume 4, Number 12 December, 1979

DATE: January 1987

* * * * * * * * * * * * *