- 1). Feed your sago palm with a commercial slow-release granular fertilizer specifically formulated for palm trees in March, May, July and September. According to Tom Broome, president of the Cycad Society, a high-nitrogen formulation of 18-6-8 NPK is effective. The fertilizer must also contain the "minor elements"---such as iron, zinc, manganese, and magnesium---that cycads need to thrive.
- 2). Watch for "frizzle top," yellowing upper leaves or crown that are clear evidence of a manganese deficiency. Spray the leaves with a solution of one teaspoon of manganese sulfate per gallon of water.
- 3). Repeat the manganese treatment in one month, then spray again the following month.
- 4). Have a soil pH test performed to check the soil if your sago palm continues to develop deficiencies. Soil should be neutral---between 6.5 to 7.0; acidic soil makes sago palms more susceptible to problems absorbing nutrients, and leads to deficiencies. You can test the soil yourself, using a kit, or take a sample to your local county extension office for testing. Follow the recommendations for correcting soil pH.
- 5). Watch for yellowing of leaves, a sign not only of frizzle top but also an indication that your sago palm has may be over-fertilized. Fertilize your sago palm no more than four times a year, using amounts recommended on the label, and remove yellowing and browning fronds with a sharp pruning shears. New ones will emerge.
- 6). Watch for orange spots on the leaves, a sign of potassium deficiency. Correct by feeding with palm fertilizer.
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