The blossom of thousands of flowers in the dryest place on earth does not happen every year. You have to be lucky. But if you are in the US during Spring, it is worth to check it out.
According to scientists, the blossom season depends on a variety of circumstances. Like the mildness (or not) of the Winter period, there needs to be substantial rainfall, a certain amount of sunlight and a moderate gush.
Though it is hard to plan to see this Bucket List tip, it is easy to spot. IN this time of age, social media plays an important role. As soon as there is a hint of blossom, the internet will be flooded with images.
Best period is half February till the end of June. Most chance in April, May and June.
More information: www.nps.gov/deva/learn/nature/wildflowers.htm