4 or 5 aluminum poles with a hook on the top end, plus some real light camo netting will serve you fine. And make the blind an odd shape with irregular sides. Ducks seem to know that bushes do not grow in perfectly square box shapes.
If there is some loose grass around toss it on the net but don't pull up grass and leave dark areas around your blind.
Oh, and be sure to pick up your hulls as you go or the ducks will see those and shy away.