A dryer appliance and additive dispensing assembly is generally provided herein. The additive dispensing assembly may be positioned within the cabinet and configured to provide an additive mist to the drum. The additive dispensing assembly may include a supply conduit, an additive dispenser, and a siphon channel. The supply conduit may extend between a fluid supply and the drum. The additive dispenser may store and dispense a dryer additive. The siphon channel may extend from the additive dispenser to the supply conduit downstream from the fluid supply. An initial flow of fluid directed through the supply conduit may create a siphon that draws the dryer additive into the supply conduit to mix with the flow of fluid and create an additive flow that is dispensed into the drum.