my best Croton effort so far.

Very, very healthy. I know it's a challenge to grow these outside in the Bay Area. I've killed many when I lived up there. They just can't handle the coolness of winter.

I have to admit..never seen a single one outdoors here. The Croton society at least rates 'Petra' as hardy to 25f. But,here we know its not the low,its the average. So,we will see.

It's not the absolute cold that kills them in Hayward, it's the continued coolness of the daytime temps during winter. Typically, when daytime temps are averaging 60ºF or less the leaves start fall off...until no leaves are left. That's my experience in Hayward, anyway.