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Effect of milk on plant growthFeatured science projectScience project video


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.

Also consider

Try to repeat the science fair project using other types of plants like radish, chili or sunflower.

Try using 4 or more pots in this experiment – eg. 2 or 3 pots of seeds watered with water, 2 or 3 pots watered with milk – for more accurate results.

The experiment can also be repeated using different concentrations of milk mixed with water.


Is water better than milk for plants -

Plants and milk -

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