How much water do bean plants need?
Don’t over saturate your plant and you’ll be fine. If you have your plant in a Styrofoam cup make sure that you have a hole on the bottom for air circulations and drainage. If you have it in a cup with no holes on the bottom cut some straw and poke it on the side (inside) of your cup. You can do this by pre-drilling the dirt on the side by bbq skewer. Make sure your straw is free of dirt to be able to let air under your plants roots.