I was recently talking to a agricultural finance company about working with them on some images of their farm clients, and they wanted to know when the almond trees in the Sacramento Valley bloom. "Mid- to late-February," was my off-the-cuff response.
But I actually have better data than that. I've been photographing the almond bloom virtually every year since 2002 (see the chart below), and have an extensive library of images - complete with the exact date each image was taken.
Over that decade plus, I have nearly 140 almond bloom images in my library. The earliest I've ever taken a photo of the almond bloom was February 12th (in 2011 - a particularly early year). The latest was on March 8th. Of course, the orchards probably begin to bloom a bit earlier and last a bit later, because I try to shoot at the peak of the bloom.
You can see in the chart below that the peak of the almond bloom typically falls in the last week of February or occasionally in the first week of March.