You can buy a concrete mix that's used for covering block.
You apply a bonding agent and trowel the mixed concrete on.
Top & Bond is one brand that I recall but you can buy it in the concrete section at HD or the like. Look for the correct material.

Thanks beacher....I forgot to come back here to check for answers...and the notification of a posting doesn't seem to work here anymore. I will check this out in Home Depot.

Susie

Pretty sure it can be done, since our renovation has stucco/parging on the foundation, which is made of concrete block. Might have to scrape the paint off first, though.

It's pretty easy to stucco over concrete block, just trowel on a coat of cement and apply the stucco color coat over it. The paint is a problem though. You can have the paint sand blasted off or I've had success using a fortified thinset mortar as the base coat. The thinset sticks well to the paint.

Thanks everyone for the tips. There should be something we can put over the paint to help the cement stick like the top and bond mentioned. I will check at Home Depot and see what they say. Lowes did not have anything, or know anything.

Either will home depot. If you have a masonry/builders supply in your area, that would be a better bet. They generally specialize in cementious products concerning masonry, plastering/stucco, and typically drywall products as well.

Another avenue is to simply contact some plaster contractors in your area for advise. Most will be happy to share that info.

We had stucco installed on our garage/workshop. The cost was about the same as siding at about $5.30 a sq ft. What a difference it made this winter. I never turned on the heat in the garage until late November. The temp remained about 48 degrees even though we were opening the door a couple times a day. We attached a sheet of 1" styrafoam and then the stucco. Our garage was already insulated in the walls but we could not believe the difference it made. just something to consider.

info on stucco over painted block is it best to remove paint. the paint is solid with no peeling or blistering.