Question
John - I have 3 sagos in my yard - two in front, one in back. The back one seems fine, but one of the two in front is sick. What puzzles me is the two front ones are side - by - side. The one closest to the house starts each spring with a new growth of fronds that start out very pretty, then, before they finally "drop" into place, they frizz on the edges, and begin to turn yellow from the outside of the frond in. By the time the next growth of fronds starts, the older growth is half yellow/brown. My father-in-law suggested cutting the old fronds off as soon as the new ones started, and spraying the plant with some poison. I am not a poison person unless I have to. I did cut off the old fronds, as well as the old fronds of the other "healthy" sago. The fronds haven't dropped yet, but they are already frizzy, and I see some yellowing. I'm guessing some sort of nutritional problem (they have had scale in the past, but I cured 'em of that) but I cannot find specific info on my problem. The sickly plant is very close  to the house, and runoff from the roof hits it dead center when it rains. Could this be a problem?
Thanks for your help
Bridget

Answer
Hi Bridget,

I am of the opinion that this condition is nutrient related, as you also suggest.  The rain drainage from the roof would cause physical damage at the site, not chlorosis on the edges of the fronds.  Having said that, if the soil is very sandy, the water may be leaching the nutrients out of the soil.  This could explain why a nearby cycad appears healthy.  Spraying any chemical without identifying the cause for the chlorosis would be a waste of money and effort.

Marginal chlorosis can be a symptom of magnesium (Mg), potassium (K), and iron (I) deficiencies.  The pH of the soil can make iron unusable, so if the soil pH is relatively high (~8-9), then the iron will be unavailable.

Magnesium deficiency symptoms differ from those of K deficiency in that symptom severity of K-deficient leaves increases gradually from base to tip of the older leaf, whereas Mg deficiency symptoms are distributed uniformly from base to tip of the leaf. Discoloration of K-deficient leaves is usually orange to bronze, shading gradually to green at the base of the leaf, whereas Mg-deficient leaves have distinctly green leaf centers and bright lemon yellow to orange (depending on the species) margins. There is never any necrosis associated with Mg deficiency, whereas leaflet necrosis is a common symptom on K-deficient palms. It is possible for a palm to show symptoms of both deficiencies on a single leaf.

Consult your local garden center for a time-released fertilizer (Nitrogen, potassium, and phosphorous) with minor nutrients (Magnesium, manganese, copper, iron, calcium,etc.)  If this doesn't correct the problem, then we can check for diseases.  Since new fronds develop, I suspect that there is not a problem with the root system.