Landscape curbing is just that, for your landscape. You need to keep this in mind and not compare it to curb you see in a parking lot. It isn’t the same as it doesn’t have the same aggregate. PSI for normal landscape curb varies on the type of sands used and ratios mixed. Most are in the 2000 psi range. You can do several things when it comes to reinforcement. Rebar like in flatwork is used for specific situations, for Lateral Reinforcement. As mentioned previously, we use cable in our curb as that may help with separation, which is tensile strength. We also use blended polymers and fiber which not only increase tensile strength but compression strength as well.