How to Refill Ortho Weed B Gon Hose End Sprayer Yourself Easily Then press the hose into the other side. While it's time to refill the hose-end sprayer, you can use the ortho weed B Gon refilled gallons to mixing the concentration. How to Apply the Ortho Weed B Gon Concentration Take your Hose end sprayer and connected it with the battery charger and spray your lawn approximately.