Science Buddies: "Ask an Expert"

Hi I am wanting to change the Ph of soil to view if it has an effect on the color of flowers or plants, but do not know how to change the Ph of soil. My science teacher said to look for a cheap method besides using lemons. Your assistance will be thanked greatly I am hoping to find a way to use this project as my Science Fair. My Science Fair is due in January.

Hi Angelica23,

I'm glad you're starting early on this project; allotting a lot of time for science, like you have, will definitely ensure better results!

There are several ways to adjust the pH of soil in a way that 1) is cheap and 2) you can measure the pH and lower or raise it the specific amount you want. As a side note, it is very important in a science project to be precise, so you'll have to note how much you are raising and lowering the pH for each test. If you Google something like "how to change the pH of soil," there are many sites devoted to gardening that offer different and varied ways to change the soil's pH. In fact, many local stores, such as OSH or Home Depot, sell relatively cheap fertilizers that you can obtain by just purchasing them without much hassle - some of these fertilizers are in tablet form - and these fertilizers/compounds affect the pH of soil. Also, some local gardening stores specifically have drops that alter the pH of soil; calling up these stores would be immensely helpful in figuring out what compounds you need to buy and how much of them you need. Although lemons and other such fruits do serve the purpose of changing the pH of soil, they are not very reliable since they aren't standardized; they also do not let you quantify how much you need to change the pH. I think fertilizers or similar compounds would probably be your best bet.

Hope this helps, and good luck!