So I decided to attempt a rock garden slope this year. I'm very new to gardening of ANY kind and hoping you wonderful people can help me.

I have a NW facing slope, mostly sunny, sandy well-draining soil, with some rocks.

So far, I have added phlox, rockfoil, wooly thyme (so cute!), and an African daisy (osteospermum) in the center. There's also some creeping myrtle along the side that my mom planted there a while ago. It didn't really take off, and seemed to have washed a bit down the slope. I didn't realize until AFTER the purchase that the African daisy is not hardy to this zone, so I'll probably be replacing it next year with something else. In the mean time, it's a beautiful plant.

Yesterday I bought a 1 gallon pot of overflowing Sempervivum arachnoideum. I made sure to get one without any flower stalks as I learned the hens die after flowering. I want to add it here and there to fill in some spots in the rock garden.

Here are my questions:

1) Dividing: Any special care I need to take to insure survival of the hens and chicks? Or can I just pull apart in small clumps and place?

2) Making them "stick": Since it's on a slope and fairly sandy, how do I avoild "pop out" or "wash out" if it rains? How long do they take to grab the earth?

3) Establishment: All over the internet it states "until established". I assume time frame is different per plant and includes lots of variables. But geez, how do you KNOW if a plant is established or not?

4) That leads to Watering: I've been giving my rock garden a good watering about once a week when no rain. I figured I had to because I only started planting there 3 weeks ago. Since the fuzzy little semps can die from too much water... how much is too much? Is there a way to individually water plants on a slope without run-off?

5) Fall color: Is there a plant suitable for this garden that will add late-summer/early fall color to it? Preferably in the white/pink/purple range.

Sorry for all the questions. :-( I appreciate any and all input!

Here is a link that might be useful: Shadara's Rock Garden Project