I wanted to test a new fertilizer, to find the best concentration for my garden. I divided my garden into four sections and put a different amount of fertilizer in each section.

My test results showed that using 10 grams of fertilizer per gallon made the plants grow faster and bigger. To follow proper scientific guidelines, what should I do next?

1. Apply 10 grams of fertilizer per gallon to all the plants in my garden.

   No. While that might make my garden grow well, it would not provide more evidence that this was the best mixture of fertilizer

2. Do the same experiment over again.

   Yes! Repetition is an important part of the scientific process. If my hypothesis is correct, I should get the same results every time I repeat the experiment.

3. Do the same experiment, but use a different fertilizer.

   No. Using a different fertilizer would be testing a different variable. I wanted to find the best concentration of the original fertilizer, so testing a different fertilizer would not help with that.

4. Publish my results, so that other scientists could replicate my experiment.

   No. Replication is an important step, but I should repeat my experiment several times to be sure that I get consistent results before I ask other scientists to try replicating it.

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