The brick method
The plants can be watered with the help of bricks. You need to fill the bathtub with ½ inch of water and place bricks at the bottom. The plant pots should be placed on top of the bricks so that the moisture can penetrate from the bottom of the pots to the soil. This method is effective if you are away for two or three days.
The plastic bottle method
You can also water the plants with the help of plastic bottles. First of all, make some holes at the bottom of the bottle with the help of a nail and place it on top of the plant pot. When you add water to the bottle, the plant will consume the amount of water it needs. Use different sizes of bottles for different plants.
The plastic bag method
Place towels at the bottom of the bathtub. Water your plants thoroughly. Place each plant pot in a plastic bag and close it nicely after blowing some air into it. The plastic bag will help in maintaining moisture and the plants will be good for close to two weeks.
The wet towel method
another way to water your plant while your are away is to take a medium sized towel and a container of water. Fill the container and place it next to the plant. Now take the towel and twirl it so that it takes the shape of a piece of rope. Put one end of the towel in the container and the other end in the pot of the plant. The water will slowly soak the towel and provide much needed hydration to the plan while you are away.