Pretty much the whole summer, bear in mind deer for example get a whiff of it and they won’t be back. We have some taller flowers and some fruit trees as the summer carries on that beg for more attention but it could be superstition. Pretty effective from keeping chipmunks, groundhogs and the like that burrow in your cinderblock that could cause major harm, the cool thing about making you own spray from peppers is that the capsaicin does not affect birds. Have never seen a salamander of any kind around here so there’s that.
They tell you to put hot pepper powder in the bird feeder with your birdseed to discourage the squirrels.