This photo was taken in the pre-dawn hours, when the mimosa's leaves are still folded closed for the night.
As mentioned, we had a couple of nasty little freezes this winter that killed back all of our tropical plants. They generally revived, but while others were rebirthing as new green shoot-lets, our mimosa tree remained barren, leafless. I feared it was dead. But it has finally shot forth bursts of leaves from the ends of its long skeletal branches. They're growing at a remarkable rate. It lives! All hail the mimosa!