When your Mexican Bush Sage gets long and leggy (like the below photo) it's time to prune it.
Typically the best time to prune Mexican Bush Sage is in December and June.
Prune the Sage down to 12" (see photo). This will allow the sunlight to reach the new growth. After pruning, feed the plant with a slow release fertilizer.
After 3 months, the Sage should be in full bloom (see below).