Once a week, all your nice leather needs to be cleaned with a properly formulated soap and then conditioned with a balsam. I personally like VeruGreen’s spray soap, and of course use Effax’s Leder Balsam to protect and condition my leather. DO NOT use a glycerine soap on your English tack! Those products are formulated for Western tack, which is tanned using a different process and requires different care. The wrong soap will fade the leather, and destroy the stitching holding your tack together.
If you do a good job wiping the sweat and dust off after each ride, then a deep clean will only take a matter of minutes. Cleaning this very dirty girth only takes me ten minutes total! So put on your favorite podcast, playlist, or tv show, and get cleaning!