Sago palm fronds should be a deep, rich green, without any brown at the center or around the edges. When fronds start turning brown, either at the tips or along the entire frond, the palm is in need of attention. Fortunately, brown fronds are easily remedied through application of the correct nutrients. It may take some time, however, for the plant to appear healthy again.
Sago palms require a number of nutrients in order to stay strong and healthy. In the absence of these nutrients they become weak and susceptible to disease. The fronds will also begin to turn yellow and brown and die, increasingly weakening the plant. To prevent brown fronds and other problems, sago palms should be fertilized at the beginning of spring, summer and fall with a fertilizer made specifically for palm trees. Regular fertilization should provide all the nutrients a sago palm needs to remain healthy.
Magnesium deficiency will cause sago palm fronds to turn yellow and brown, appearing burnt or damaged at the tips and edges. An application of magnesium sulfate will help correct the problem. Any mulch around the tree should be removed before applying the magnesium sulfate at the rate recommended by the manufacturer. Water the sago down to the roots. The mulch should then be placed back around the tree.
Manganese deficiency is different from magnesium deficiency and results in a problem referred to as frizzy or frizzled top. Fronds appear brown and twisted in the case of manganese deficiency. Like other nutrient deficiencies, the solution is to provide the necessary nutrient. Remove the mulch and apply manganese sulfate at the rate recommended by the manufacturer. Water the tree deeply so that the manganese will reach the roots of the tree. Put the mulch back in place after watering.
It is tempting to remove the brown fronds right away so the palm looks healthier. Doing so, however, could make recovery more difficult for your sago palm. Fronds should be left in place until they are entirely brown and dead. If they still have any green areas, even at the base, leave them attached to the palm. Until the frond is completely dead, it is still feeding the palm plant.