Disclosed is a blowing device for a rotary air lock, comprising a flushing gas stream that is fed by a gas supply line (12) in order for adhering material to be flushed and blown out of at least one compartment (20-24) of the rotary air lock (20-24) when said compartment is located next to a product outlet of the rotary air lock. A blowing unit (30), which comprises at least one blowing tube (32) and is located in a feeding shoe (10) that is arranged at the product outlet, directs the flushing gas stream to at least one compartment (20-24) of the rotary air lock.