I just found out that they had their big weekend with the festival last weekend. What brought this to mind is seeing a few trees in bloom in Lee Park yesterday.
The few pics that the local paper has on line were not that great so not sure how the trees look, I do know that the flowering of the trees is not for a real long time.
Also in the Great Trinity Forest there wasbe a hike to see the Texas Buckeye in bloom a couple weeks ago,
http://www.texasbuckeyetrail.org/
They still should be in blossom this week (I've taken the hike a couple times and it isn't bad but I would wear some shoes that you would not mind getting muddy).
If enough people would want to hike out there this Sunday after lunch I can pretty much guide a group out there since I've been on the trail a few times and the trail is reasonably well marked (though several times a year it is under water).