Recognizing Nutritional Disorders of Floriculture Crops Jared Barnes • www.harvestandsnow.com • [email protected] Symptomology of Macros Symptomology of Micros Nitrogen Deficiency Boron Deficiency – Initial: lower leaf yellowing, – Initial: smaller plants, upper leaves discoloration (purple, etc.), smaller distort and become thick and/or brittle plants – Advanced: lower leaf yellowing, failure – Advanced: plant yellowing, lower leaf to flower necrosis Boron Toxicity Phosphorus Deficiency – Initial: marginal browning on lower – Initial: smaller plants, lower leaf leaves purpling, darker leaves (hard to see – Advanced: marginal browning on upper without healthy plant comparison) leaves, leaf distortion, lower leaf – Advanced: lower leaf necrosis, leaf drop necrosis

Potassium Deficiency Copper Deficiency – Initial: necrotic spots on lower leaves, – Initial: leaf bleaching or spotting lack of stem elongation, upper leaves – Advanced: spot sizes increase appear healthy – Advanced: necrotic spots increase in Iron Deficiency size, failure to flower – Initial: interveinal chlorosis or yellowing on upper leaves Calcium Deficiency – Advanced: interveinal chlorosis or – Initial: middle and upper leaf necrotic yellowing spreads to lower leaves spots, reduced root growth – Advanced: necrotic spots enlarge, entire Manganese Deficiency plant collapse, failure to flower and – Initial: yellowing (variable- marginal, stem topple whole plant, lower leaf) – Advanced: yellowing intensifies, Magnesium Deficiency necrosis on upper leaves – Initial: marginal or interveinal yellowing – Advanced: leaf bleaching, flower color Zinc Deficiency change, lower leaf necrosis and/or leaf – Initial: smaller plant size, some drop distortion of flowers – Advanced: leaf necrosis, interruption of Sulfur Deficiency flowering – Initial: upper leaf yellowing, smaller plant size – Advanced: entire plant yellowing, red discoloration, lower leaf necrosis

See my thesis for more information. http://repository.lib.ncsu.edu/ir/bitstream/1840.16/6025/1/etd.pdf