Hi Keving63,

What are you planning to mulch with? Sedum's spread on the surface, so in order for them to spread, the stems need to be in contact with the soil so they can root. If you use a coarse mulch around them, you'll neeed to gradually keep the mulch pulled back so the spreading stems are laying directly on the soil if you want them to root and keep spreading. There are a lot of weeds that won't be killed by mulch, so definitely pull out any you see before mulching and any you see coming up through the mulch.

Good luck,
Skybird

Keving63, I have tricolor sedum planted in my front yard and used 2" deep cedar mulch in between. The plants have grown nicely but not expanded at all beyond their mulch "pods" (great hint on gradually pulling back the mulch so they can fill in, Skybird!). The cedar does keep the weeds down, though, and the few that pop through pull up very easily.
Hope that helps!

ditto- sedum won't root in mulch, though it can be encouraged TO root if you mulch lightly over any growth that's gotten leggy.

I'd pull or hoe the weeds, then mulch around the bushes, but leave room for the sedum to spread- mine's doubled in size in the past month (it got 'heeled in' and spent the winter in its pot, outside- so it was a thrilled as I am to see the weather breaking)

Thanks for the advice everyone. I'm going to mulch around the shrubs only, until the sedum spreads into those areas.