see the link below

Here is a link that might be useful: stepables

Love your design. Will it have a lot of traffic?

If so, it will need a really tough plant since the foot will land squarely on the plant and be a heavy footfall as it is stairs. I can't think of a groundcover that would take a lot of traffic well. The one I was going to suggest is creeping camomile. My path has the foot landing on wood mainly. I love it's look more than any ground cover except Scotch or Irish moss which promptly die for me. Also it is wonderfully drought tolerant.

If you don't have luck with ground covers pebbles might work.

well, might get a couple people on it per day, but I rethought the idea of stuff between the bricks, and now think that around them should be enough - to keep weeds down!

I looked at the link - very interesting. It suggested scleranthus so I'll need to find a place that sells that. Creeping camomile might work too!

thanks for the help!

If you put a black plastic covered by a layer of leveling sand under the bricks that should stop any weeds from coming up. A few may grow inbetween now and then.
But it's probably too late to do that.

Look at Dymondia, it's a really tough and drought-tolerant ground cover and will handle foot traffic.

A staircase on a fairly steep hill I have always admired was in the garden of Harland Hand of El Cerrito. He lined his path with white flowering and silver leafed plants, which glowed in the moonlight, which made the stairs more discernible at night, a nice added safety feature. He used succulents as well as trailing plants.

Erigeron karvinskianus is one of my favorite trailing plants that spills nicely over banks and slopes. Graced with a good sense of design, it self-sows readily into cracks, looking much better in it's chosen spots, than the ones I find for it. It has small white flowers year around.

Here is a link that might be useful: harland's garden

gobluedjm, it's not too late to line the steps with plastic - i can pull up the bricks from the 5 steps that are finished and do that. Good idea!

davissue_zone9 - I like the idea of light colored plants to allow visibility at night: might help prevent people falling down drunk in the garden (it's an unfenced community garden)! ;)

I will look into Erigeron karvinskianus and Dymondia. I love the look of Scleranthus but have only found it two places online. Is that something I might find at (shudder) Home Depot, for cheap? Or is it too unusual?

Good! I think you'll be much happier. I was thinking you might have to pull up the rebar ones also. But if you dig out more soil you won't have to take them up. That's work!
I've taken out old railroad ties someone put in.

You might check with a local nursery on ordering for you.
You might also check Lowes website on building steps etc.
Lots of good ideas.