
Milk vs. Water for Growing Tomatoes
Easy
Can milk help a plant grow better than water? You plant tomato seeds in two pots with the same soil. One pot gets 500 ml of water each day. The other gets 500 ml of milk each day.
Over 14 days, you measure the height of the plants. The water-fed tomatoes sprout and grow steadily. The milk-fed pot produces no sprouts at all. The soil in the milk pot hardens and starts to smell.
Hypothesis
The hypothesis is that using milk to water plants will help them grow better.
Method & Materials
You will plant tomato seeds in two pots, one watered with water and one watered with milk. You will measure the height of the plants every day for two weeks.
You will need tomato seeds, two garden pots, soil, milk, distilled water, a measuring cylinder, a ruler, and a black marker pen.
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See what’s includedResults
The results showed that the tomato plants in the pot that was watered with water grew very well, while none of the tomato seeds in the pot that was watered with milk germinated. The soil also became very hard and gave off an unpleasant smell.
Why do this project?
This science project is interesting because it explores the effects of an unconventional watering method on plant growth.
Also Consider
Consider repeating the experiment with other types of plants, such as radish, chili, or sunflower. You could also try using more pots and different concentrations of milk mixed with water.
Full project details
Additional information and source material for this project are available below.Related videos
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