Science Buddies: "Ask an Expert"

I have three plants that have chives seeds. One, I am watering with only water, one with only milk, and one wih 50% milk 50% water. My milk plant is not growing at all. Do you know what is stopping it from growing? I am watering my milk plant with 1 8th of a cup milk. Am I doing anything wrong?

It doesn't sound like you've done anything wrong. In fact, you just found an interesting result! Apparently plants don't like milk.

When you write up your results and conclusion, try to come up with an idea of why plants don't like 100% milk. There could be a number of reasons, but I can also think of one thing that might be happening. Milk spoils if it isn't refrigerated, so think about how that might be affecting your plant. Also, think about how milk is different than water. With 100% milk, is there enough water for the plant?

You can read this page for an idea of how to measure your results: https://www.sciencebuddies.org/science- ... owth.shtml

At the end of your experiment, take a look at the 50% milk 50% water plant and see how it compared to the one with water. Is one healthier/taller than the other?

Good luck and let us know if you have any more questions.

Thank you for your reply. I am still wondering though what it is about the milk that is bad. Sure, it can spoil but is that the only reason it is harming my plant? Maybe it builds bacteria, or its ingredients are harmful to the plant. Could you maybe give me a bit more info on this? I thought milk would help the plant, because it has vitamins. Milk helps us grow, so why doesn't it help plants grow?

Thanks for your time and effort

Hi milkplant,

Spoiling means that bacteria is growing and eating the milk. And yes, it's also possible that some of the ingredients are harmful to the plant. While every living thing needs certain types of nutrients, it depends on the organism. Plants actually make their own food using carbon dioxide in the air, water, and energy from the sun. They also need nitrogen from the soil.

The vitamins we need are very different from what a plant needs. So, many nutrients in the milk might be unnecessary for the plant, and it won't use it.

I would definitely look for signs of mold around your plant. My best guess is that bacteria/fungus or lack of water (there might not be quite enough in the milk) are killing it.

I'm not a plant expert though about vitamins. I'm not sure what effect they would have on the plant, if any. It's possible the plant just ignores them, or in large amounts, they could be toxic.

Thank you so much for your reply! It was a big help!