The hypothesis that using milk to water plants will help them grow better is disproved.
Watering plants with milk may provide additional nutrients for the soil, but the transpiration of water from the soil may cause the concentration of milk solutes to increase and make it hypertonic. This will make the plant wilt because they cannot absorb water from the soil. Milk will also cause bacteria growth and attract insects that can harm the plant and its roots. Plants watered with milk usually wilt and die after a few days or weeks.