After determining the pH of the soil in your garden, find out about different ways to improve your soil from your local nursery or by doing an Internet search. Then, test out the best method to improve your soil's pH with this science activity.
Examining Your Results
You should now have a good idea of which additives will work and which additives will not work to treat your soil. To help narrow down your choices of which additive to use, you may want to consider the cost of the additive, how much work and preparation is needed to use it, and whether it is organic (natural). If you still haven't picked just one additive to use, do a comparative study by adding one additive to one section of your garden, another additive to a different section, etc. See if the additives affect plant growth, either negatively or positively. You can also expand this by doing a longitudinal study. Keep your soil samples and retest the soil every month or so to see which additive keeps the soil at the right pH the longest.