I am currently calling this an Aeonium haworthii or Pinwheel because that's how it is labeled in The Complete Book of Cactus and Succulents. Personally, I think it behaves and looks much more like an Echeveria, but what do I know? They are easy to propagate with cuttings, just poke the stem into the soil and keep it moist. My aeoniums seem to suffer the most from hot blazing sun in the summer.
Next we have a beautiful Crassula Tetragona. These are used as pine trees in bonsai. But, I like to let them grow wild in my garden. They have a nice deep bluish green color to the leaves. They grow to about 4 feet tall and about a foot wide. They flower from the tips of their branches. The blossoms are clusters of tiny creamy white flowers with a flat top. They remind me of Queen Anne's lace, but slightly smaller.
They are hardy to about 40 degrees, but I've had good luck getting them through frosts by throwing a sheet over them. I've written about crassula tetragona on the blog too. They do not seem to mind the hot, southern California sun here.
These crassulas are so easy to propagate even my dog knows how to do it. He sometimes knocks branches off when he's on patrol in the garden. I keep finding them coming up in odd places. When they are laying on the ground crassula tetragona form roots just under the leaves that reach down to the soil. Then the ends of the branches grow upwards to form new plants. The normal way to propagate these cuttings is to put a branch into the soil a few inches and keep it moist for the first few weeks.
All crassulas are drought tolerant and most will freeze if left unprotected in the garden. I love succulents because there are so many different shapes, colors and kinds. I can group different plants together since they all have similar growing requirements. I like the contrast between the light green aeonium rosettes and the dark green spiky crassula leaves. And eventually they flower. Happy gardening!