Whenever I water anything in a container - I water it at least twice. This is for anything I have at home, or when I was working at a nursery. Usually you don't get a thorough soaking with the first pass. After about 15 minutes, go back and give them a second drink. When I used to do tomatoes on an apartment balcony in large boxes, I used grass clipping as a mulch. Kept the moisture more even. Alex