What's wrong with my princess flower tree?

[sfdoc]

Hi folks,

I live in San Francisco and have two princess flower trees in front of my house in containers. They get full sun (maybe too much?) and are beginning to flower alot but the leaves are dry around the edges and falling off. The leaves begin as crimson brown and never turn green. The trees have excellent drainage but is it possible that I am watering too much or too little? Right now, I give a thorough soaking every 2-3 days because I was advised to water them whenever my water meter reads dry. Please help! I love these trees so much and can't figure out what to do. Thanks!
[img]https://i1049.photobucket.com/albums/s395/sfdoc79/princess2-1.jpg[/img]
[img]https://i1049.photobucket.com/albums/s395/sfdoc79/princess1-1.jpg[/img]
[img]https://i1049.photobucket.com/albums/s395/sfdoc79/photo.jpg[/img]

[rainbowgardener]

It's really hard to tell without seeing pictures. Instructions for posting pictures here are in New to Helpful Gardener? under Helpful Tips and Suggestions for New Members.

Offhand, without knowing any more, that does sound like too much watering, but that would depend a whole lot on how big the containers are. Small containers dry out a lot faster than big ones.

[rainbowgardener]

How big are the containers?

[sfdoc]

Containers are 16x16. When I measure the moisture, the edges tend to be much wetter than the center.