One of my outside sago palm plants is covered with white spots. Extremely heavy on and near the base and stems. Spotty on the outside ends. I've sprayed with a scale and white fly repellent, but so far it has had no effect.
Certified GKH Gardening Expert
This can be a sign of scale, or it can be a normal occurrence. This article will help: https://www.gardeningknowhow.com/ornamental/trees/sago-palm/white-spots-on-sago.htm