To two different varying degrees.
We've talked about how they pump warm water throughout the property in shady areas for the turf. We did so around the same time Alabama was doing the same thing with the turf in BDS.
The trees? The landscaping? Now we are into a genus and species discussion. They play this time of the year because those plants always bloom at the same time every year. Their genus does annually in the spring (IE: azaleas) but the species varies when they bloom. The different trees and landscaping plants around the property bloom at the same time. It isn't by control, it by the choice of the genus and species. Mother Nature is "A Tradition Like No Other."
It's not a lot different than a rose bush. You can have one that is a running rose, another that's a bush, but they are both roses who bloom at different times. (IE: The bush roses I have bud every year at the very same time the Bradford Pears bloom.) It's the third or fourth week of March, each season.