Existing plumbing fixtures, such as hose bibs, sillcocks, spigots often become loose over time due to stripped holes of securing screws, rusted screws, deterioration of material behind, or inadequate installation from the start. A fixture accessory adapted to tighten the loose fixture can include a plate or split-plate assembly that can slide behind the fixture to secure it without removing the fixture. The fixture can be secured to the plate by a variety of attachment means such as screws, bolts, clamps, or an adhesive, and the plate can be secured to the wall by a variety of attachment means. Also disclosed is a system to firmly hold a freeze-prevention cover over a plumbing fixture.