When it comes to choosing boulders, my favorite place by far is Southwest Boulder & Stone. Don’t be fooled by their smaller lot in Pacific beach, their large lot outside Fallbrook is the way to go. The pile of boulders in this photo is one of about 20 varieties of boulders that you can choose from, and they will let you pick any boulder in the pile, even if it is on the bottom.
When you choose your rocks, start by deciding whether you would like one that is smooth and rounded or jagged and rough. That will let you eliminate 50% of the options. Then start looking at color and texture of the stone. If you want the boulder to look natural in the landscape, you will need to bury at least one third of it, so you need to select boulders that are larger than the final desired result.
In this case, we were looking for boulders to use as casual seating, so they needed one side that was flattish and smooth-ish. I think it is tons of fun climbing around on all the rock piles!