Green Grasso Holm's answer is right, and a good explanation of the difference between the words "raw" and "uncooked".
In your particular sentence about washing, I most often hear things like:
"I should wash the vegetables before cooking" or
"You should wash the produce before starting to cook"
Produce in this case is a noun which means fruits and vegetables.
Another thing to note is that the phrase 'wash up' is not used with an object.
"I washed up the vegetables" is not grammatically correct, it should be "I washed the vegetables."
"wash up" can only be used without an object. In this case, what you are washing needs to be implied through context.
Here are some examples:
"I always help mom wash up after dinner" - Here it is implied through context that the speaker and their mom are washing the dishes and possibly also the kitchen counters, depending on how messy cooking dinner was.
"The kids were playing in the mud again, so I told them to go wash up before we had to leave" - Here it is implied that the kids were washing themselves, or possibly just their hands, depending on how muddy they were.