Gardeners often approach their hobby scientifically. Over the years, they figure out the most effective ways to produce high yields of tomatoes from their plants. In their amateur research, home tomato growers study their tomato plants' measurements. This may include the need to weigh a tomato plant that is fully grown. Weighing a mature tomato plant takes less than half an hour if you are prepared.
Dig up the tomato plant with a shovel. Do this gently, to keep the root system as intact as possible. Once the roots are loose, pull the plant out of the soil. Shake the loose soil from the roots.
Move the tomato plant to the grass or patio, and lay the tomato plant on its side. Use a rag to wipe soil and moisture from the roots.
Weigh the empty plastic bin on the bathroom scale. Write down this weight on a piece of paper.
Place the tomato plant into the bin. Check to make sure that no parts of the tomato plant are hanging over and touching the floor, as this would result in an inaccurate weight.
Check the weight of the bin with the tomato plant in it. Write down this weight on the piece of paper.
Subtract the weight of the empty bin from the weight of the full bin. The result is the weight of the tomato plant.