
California poppy is the official State Flower of California. Most Californians are familiar with it. We certainly know what color it should be. With few exceptions, it is bright and clear orange. Some, particularly within desert climates, are golden or more yellowish. White and pastel purple California poppies are rare aberrations. When I was a kid, finding one or the other was comparable to finding a four leaf clover for kids in Ireland. They were even a bit better though, since plants that bloomed with variant color bloomed with more than a single flower.
When I was about a freshman in high school, I found both a white and a purple California poppy just a few feet apart from each other. They happened to be at the Portola Monument in Montara, near where the Portola Expedition discovered San Francisco Bay. It was too early for seed, and I did not return for seed later. Besides, most of such seed produces plants that bloom with typical orange floral color. Nonetheless, at the time, I was very pleased to have found two very rare aberrations.
In more recent years, varieties of California poppy were developed. Some bloom with white or purple bloom. Others bloom with pink, red or yellow flowers. Some have double flowers. They are readily available from mail order catalogues and nurseries, as well as online. White or pastel purple California poppies are no longer rare or special. This sort of takes the fun out of finding one.
I suspect that the white California poppy in this less than exemplary picture is natural. Poppy seed was not likely sown here intentionally. Nonetheless, I do not know. Now that it is no longer special, its source is not so important. Realistically, their typical bright orange floral color is the best anyway.