Question
I live in California, and zone 8.5, and just installed a retaining wall.  It has the angles in each corner making 40 little pockets that I'd like to fill with something so weeds don't grow in them.  The pockets are about 3in square.  Because this is in a busy public walkway I'd like it to not spill out very far if at all.  There is also a large tree in front of them so they only will get about 3-4 hours of morning sun as is comes in under the tree.  So, I'd like to find something that would go in these holes, not grow out or spread much, and needs little to no water.  Thanks.

Answer
Hi Brian,
Thanx for your question.  There are over 400 different types of sedum and many are low growing and spreading.  Many of them bloom in yellows, whites and pinks.  Most are drought tolerant and some will tolerate some shade.  I'm including a link so you can look at the various sedums and see which ones might be best for you.

http://www.desert-tropicals.com/Plants/Crassulaceae/Sedum.html

You might also want to consider creeping thyme and some of the other thymes.  I hope this helps.
Tom