Stone Garden Border
The next day you're ready to put in the stone border. Wet the entire project down as always, it will be especially important to be sure to wet the border very well for the next 4 days, every morning. The rock will really draw the moisture from the concrete and it will crack or lose stones. Mix the concrete fairly thick, you'll want it to support the weight of the stones as you place them.
Starting at an end spread the concrete about the thickness of the rocks you use, smaller rocks are easier to do but it is up to you as to size. I do about a 5 foot length at a time with the concrete and let it dry for about 5 minutes before I place the stones. As you get going you'll be spreading the concrete and going back to the first place and setting the stones so it goes very fast, no waiting time. There is nothing to it, just press them down into the concrete to about half their depth. Don't do these one at a time unless they are very large rocks, it would take you forever, just spread some out in your hand and press them in, I then go back and add a few to any large spaces I have. If you have kids around they may enjoy helping you with this part and won't get to dirty, wait a minute, they're kids and will get dirty..
Go around the entire border like this. Then start at the beginning again and use a small brush to knock off any concrete you have on the rocks and to smooth out the concrete between the rocks, a little water on the brush helps. I like them very close together but again this is up to you. You won't need to take the rocks to the bottom of the inside since it will be covered with soil, but I do take the concrete to the bottom for a little extra strength. Very easy. You can also use other things like broken pottery or tile instead of the rocks.
If at any time in the future a stone comes off don't bother to mix up any concrete, just use a little silicone caulk to replace it and it will stick like crazy. This boarder is about 35 feet from end to end and it took less than 2 - 80 bags of stucco, mortar will work fine here also and actually it's a little coarser and stiffer so it may be easier to use. About 3 hours later I have the border finished, make 1 more lap around with the brush cleaning up any extra concrete from the rocks and smoothing between them. This will last for many years and now onto the soil mix. Be sure to wet these down every morning for 4 days. Click here to continue to mixing your own cactus potting soil.