If you are growing in a swamp maybe you should be growing rice or water lillies. Either that or make some raised beds. For weed, you'll want the soil to dry out at least occasionally. Over watering is a common mistake. You should not water until the soil around the roots is almost completely dry, then water thoroughly. I use my hydro nutrients at about half strength roughly every other time I water. I don't worry about watering my outdoor plants unless it's been hot and dry for about a week. If it gets real hot and dry, they may need water every other day if they are established, or daily if just starting out. During real hot weather I just check them every 2 days or so, watching for any signs of wilt. Of course too much water is better than not enough, but a surplus will also cause wilting and poor development. I guess that's better than death.