Maybe it's too hot there? We're actually very mild in early summer. Lots of fog. Could be that. But the temperamental aspect of it still eludes me.
Some local news from South Africa where this plant is being touted as a tree of life, for the curious...
https://www.timeslive.co.za/ne...
Here it's pretty universally used as a hedge plant, because it is infinitely prunable and shapeable. The one in the picture above would have been as wide as it is tall, had I not taken a pair of shears to it fairly regularly.