Mountain laurels are slow growers, so I don't think it would get beyond 5 X 5 for a very long time. They do require acid soils....

I would *guess* my soil to be on the acidic side, given the dozen pine trees around this yard, but I'm not sure. Since these are already in the ground, should I test it and, if not acidic enough, add some garden acidifier?

Contrary to popular belief, plants have almost nothing to do with how acidic a soil may or may not be. Soil pH is determined almost exclusively by the underlying mineral content and to a lesser extent, the amount of rainfall. Plants just don't factor into the equation at all :-)

And the soil does not need to be heavily acidic...mildly acidic (6.0 to 6.3 or so) will suit them perfectly well. If you can grow gardenias, azaleas or camellias, you can grow kalmias. They prefer a well drained, organically rich and consistently moist soil (don't allow to dry excessively) and provide some protection from hot afternoon sun.

btw, Olympic Fire is considered a dwarf or compact form and is unlikely to exceed 5'x5'. Carousel is a much more robust grower and can get to 8-10' tall and wide eventually.

Wow, these sizes are so confusing! My carousel says 4 by 4 on the tag and on the info from the nursery! I did not give it 8 to 10 feet of room to grow, at least on one side... I picked these because I thought they were supposed to be on the smaller side. I only put 4 feet between the two. Is that going to cause a problem?

I only have two azaleas - not my favorite so I removed a bunch - but there are at least a dozen in every other yard on my street. They grow like weeds here, so I guess that's a good sign. And I added so much compost to this bed. I hope not too much compost. Shaded from afternoon sun. Thanks gardengal.