Portland desert garden drive-by (under construction)

What a difference a block makes! I regularly drive a path just one street over from this garden, I had no idea this was just around the corner. Granted it's new—under construction even—but it's already looking pretty fabulous...Last weekend I attended a couple of Hardy Plant Society of Oregon open gardens and parked just a half block away from here. I was making a U-turn to head home when one of the agaves caught my eye—not literally of course. Wowsa!
It looks like the visionary gardener at work here is planting islands of plants and rocks and then will be spreading gravel out between them. Of course that's just my guess.
I do worry when I see plants like those blue chalksticks go in. Obviously I flirt with danger and plant many things that are not reliably hardy here, but I always hope other gardeners haven't been sold a bill of goods and think they're planting long term plants when really an average winter might take them out..
Looks like an Agave parryi 'JC Raulston', that's pretty much bullet-proof here.
I'd be guessing if I tried to ID this agave, but I do think it's one of the hardy varieties.
I love this vignette most of all. It's a crevice garden pyramid!
Hmm... what the heck?
Folks that's a Leucadendron 'Ebony'! Hot damn, definitely not hardy here in an average winter. These are some hard core zone pushers gardening here.
Zone pushers who love rocks.


Agave ovatifolia
I love the fact there are a couple of trunking Yucca rostrata and then several other smaller ones that will begin to trunk very soon. It's a great mix of sizes. 
This agave has me stumped. Anyone care to make a guess?
Nice opuntia, more chalksticks...
The plantings up near the house are obviously established, which has me guessing that maybe the current residents have been here awhile but are just getting around to removing a front lawn and taking their garden style all the way to the street?
This is definitely one I'll be watching!