After reading about Barry the San Francisco Florist at Tattered and Lost Vernacular Photography, I had to look through my San Francisco flower vendor cards. You don't see flower vendors on the streets in San Francisco like you used to.
Here are the backs of the cards. The first one was written in 1923.
San Francisco - Feb. 1 - 23
Arrived yesterday A.M. with my friend and shall be here over the week-end. Mildred will come over to me tomorrow + with me two nights. Mr. Hayes telephoned me ate this afternoon from our house + said they were suffering with the extreme cold temperature down to 28 degrees and snow on all the surrounding mountains. So cold then the house wasn't comfortable.
No message on the second card.