I'd take the strip groups and put them in a sinkful of hot soapy water. Reds, Oeanges, and Purples have all run on me in the past. If there is no color in the water after soaking ten minutes or so, I would rinse and hang over plastic hangers to air dry.
Since you'll be assembling next to whites, I would still use color catchers the first couple times it gets washed.