To begrime; soil with mud; daub; smear.
To knead dough; stir dough previously kneaded to a proper consistency before baking.
To meddle; interfere.
To work persistently or laboriously; be occupied in working (e.g. in the earth, rake among dirt, etc.).
To become soft; become moist, as damp earth.
To injure (anything) by rough handling; handle roughly.
To soil or dirty; to mess up; to clog.
I don't want to gunk up my new shoes, so I'll wear the old ones in the garden.