You can try just lightly spraying the exposed stem early in the morning. And if you want water the media lightly but try to go only at the edges, since we do not know if it has managed even one root. Usually if there is at least one fully opened leaf then that is the time I will resume more watering.
From what you said, your area is in the inland side of San Diego, so it is hotter area like ours. Is this plant positioned in full sun? I would move it to part sun only, ideally morning sun area only. When it is a cutting and temps are so extreme, it gets so stressed especially if area is very dry heat. So position in some dappled sun area, if you have no intention of removing the inflo, this will help lessen the heat stress.
