I use an Ortho Dial N Spray Hose End Sprayer. Only $12
Can put 32 gallons of fertilizer. Fill with water to top (32 ounces) and set for 1 ounce per gallon.
Attach it to the hose, and you're good to go.
The actual one I bought has been discontinued, but this seems to be the replacment.
http://www.homedepot.com/p/Ortho-Dial-N-Spray-Hose-End-Sprayer-0841010/204758731#product_description