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Before we talk about ways to test your soil PH, I want to explain why.
Testing your ph is essential to a healthy and thriving garden. Most vegetables and fruits grow in a ph of 6.0-7.0. However, some plants like asparagus for example like more base soil, Ph 6.5-7.5. And on the opposite end of the spectrum you have blueberries that love the ph to be right at 5.0 or a little under.
Having the proper ph for your plants allows nutrients to be able to be absorbed by the plant. No matter how much n-p-k and micronutrients are in your soil they can’t be properly absorbed without the correct ph.
Test at your local Cooperative Extension Service. Cost: Free! (In most cases)
I highly recommend getting your soil tested at your local cooperative extension. Especially if you are starting a new garden, you will want to bring in a sample. They not only give you a ph but also important information about the nutrients in your soil. Oftentimes they will offer suggestions for fertilizer amounts. I learned to interpret my own results since I don’t use the synthetic fertilizers they suggest and prefer to use organic fertilizer.
At my cooperative extension you must bring in completely dry soil to be tested. Take samples from several areas of the garden bed you would like to test. Don’t just skim the surface, dig several inches deep for your samples. This will give you the most accurate results. Lay it out to air dry. I spread mine on a tray in a thin layer so it goes faster.
Where I live, you turn in the soil sample and a few weeks later get the results in a letter in the mail.
I test my soil every 3 years with the cooperative extension. The results give you an exact ph, that you can be confident is correct.
2. Litmus Paper. Cost: $8.95 for a 16ft roll of tape. I use about an inch per test, which means each test costs 4¢
On the off years that I’m not testing my soil at the cooperative extension, I use litmus paper. It gives a great estimate. Estimate being the key word.
I collected three soil samples from different beds. Collecting more soil is better than collecting to little.
Put your soil in a container. In my case I used the kids dishes for this purpose… ahem…sorry kids! Then put a little bit of spring water in there, less is more in this case. You just want enough to saturate it a little. Use spring water because it has a more neutral ph than tap usually.
Next stir and let it sit for an hour. I know, it’s hard to be patient. You know how hard it is to pick off all the blooms on your first year of strawberries? And you cringe a little at each flower? Guess what?! This is easier. Whew. Only an hour of waiting.
Then its time to test. Read the results after about 30 seconds.
I like to add a few controls in my experiment to make sure the paper is still working. This paper has lasted since 2016! Above you see the “estimates”
Are you ready for the actual numbers?
I had my soil tested at the cooperative extension recently so I can give you exact numbers in comparison to the litmus test.
Vinegar: 2.4 (according to google)
Vegetable Garden: 6.2
Spring Water: 7.5 is my guess. Obviously this can vary based on source.
Baking Soda: 9
My vegetable garden soil in the litmus test doesn’t look to be quite a 6. And blueberries look a little lower in PH than 4.9 to me too. That is why the exact reading from cooperative extension is nice.
If I were to read this without knowing the actual exact numbers, I would leave my blueberry soil alone and add a little lime in the vegetable garden.
That is exactly what I’m going to do anyway! See how the estimate can work too?
3. Ph Soil Test Kit, RapidTest. Cost $9.88 for 10 tests. ~99¢ per test.
I put this test last for two reasons. One, it’s the most expensive. Two, it is difficult to read.
Another unfortunate thing about this test is the minute amount of soil being tested. I’m not sure how you can feign accuracy from such a small sample.
There is one positive. This test is being sold in just about every garden store.
Here’s how this test works. You put your miniature amount of soil in the side and stop at the fill line. Then break open the capsule and shake out the powder. Fill the rest with water and give it a shake or two. Oh and don’t forget to put the lid on, nice and snug before shaking.
Now it’s time to attempt to read the results…Looks like 6.5? This is my vegetable garden soil by the way. Comparing a translucent color to a solid one just doesn’t quite work for me.
I took it indoors to try again. In this light it looks more like 7 perhaps. Anyway as mentioned above the actual exact results were 6.2 from this same garden bed.
All in all, it’s similar to the litmus test in that it is an estimate and a good way to make sure your not way off the mark as far as ph goes.
Above is the paper I use. I bought it on amazon back in 2016 so I’m not sure if the colors have changed or if the photo doesn’t match up.
This is the kit for option #3. I’m pretty sure I convinced you all not to get this one but I’m putting it up for anyone who wants to give it a go.