Is it easy to roll a trash can over it?

Each rock is rounded on the top edge next to the space which makes the gap more pronounced. I guess it would depend on how big the trashcan wheels are, but I am guessing you might have an issue. I used the mold for a walkway and it worked great, but I don't roll a trashcan over it or put anything on it. I think your chairs and table would probably wobble.

Although the QUIKRETE® Walk Makers can be ideal for creating patios or walkways, if there are going to be chairs or a table placed on the patio, or trashcans rolled down the walkway, you should instead consider pouring a concrete slab, using Pro Finish QUIKRETE® Crack Resistant Concrete Mix #100668, or QUIKRETE® Concrete Mix #1101. A concrete slab provides a solid surface, without the presence of the many joints between the “bricks” and “stones” that would be there if a Walk Maker were used. These joints, as well as any irregularity in the surface, depending upon how each 2-ft x 2-ft Walk Maker area was finished, may potentially cause instability of items placed upon the surface. Of course a slab will require control joints to allow for movements caused by temperature changes and drying shrinkage, but these would be much more infrequent as well as being regularly spaced.