This year to make the job a little bit easier we have our outdoor washing station. It's simply an old Belfast sink with a bucket underneath the plughole to catch the water and a short length of hose from the outdoor tap next to it.
We give the veggies (and plant pots, wellies etc) their first rinse here and it saves the pipes in the kitchen sink from getting clogged up with soil. The soily water drains into the bucket underneath and we use this to give the veggies in the tyres a drink. Very environmentally friendly in my opinion as the soil goes back to where it should be. It's surprising how such a simple idea has improved things.
...and immediately give all the trimmings to the chickens, so they get a fresh tasty snack too. You should see them lining up by the fence to watch me preparing their salad!