Soil pH is important, but often people see the number listed and have no meaningful way to measure it themselves. While testing soil pH used to be a hard thing to do or require a lab, today it is commonplace, easy and can even be done in some DIY methods. We’re going to look at the different ways you can test soil pH and cover the steps you need to take to get an accurate reading.
The Different Methods You Can Use to Test Soil pH
In general there are three main methods available to test the pH of your soil. First and easiest is likely going to be a simple pH meter. These are relatively cheap, but also often are a situation of “you get what you pay for” so you’ll have some due diligence in selecting a good one. Next up there’s the more reliable, but also more time consuming, pH strips. These are chemical tests that change color when exposed to a moist substance. While they can fairly easy to use they are not so nice for people who have trouble distinguishing between color gradients. Finally we have general DIY testing. This will not give you a number, but will essentially tell you if your soil is acidic or not. This can sometimes be useful, but is often only used as a last resort due to it’s inaccuracy.
Breakdown of Each Soil pH Test
Instructions may vary from test kit to test kit, but these general guidelines will let you know what you’re getting in for when you start the process. Additionally each tester has it’s own pros and cons which we’ll layout below
Probe Based Soil pH Tester
How to Use a Probe Based Soil pH Tester
Soil pH testers are probe based meters that measure the pH across a moist medium. Most testers have two metal spikes that come out of them, but some probes are self contained and only have one sampler. To use one of these probe based testers you only need to insert it into soil and wait 10 to 15 minutes for the pH to read on the meter. When you’re done simply extract the probes and wipe them dry and the device is ready for use again.
Advantages and Disadvantages of Probe Based Soil pH Tester
The major advantage to these probe based soil pH testers is their ease of use. Simply stick them in moist soil and get a reading within 10 minutes. They’re small, portable, reusable, and just about anyone can use them.
The major downside to these testers is the flood of terrible products on the market. Many soil pH testers that you can find on amazon are just the same tester packaged by someone else. The meters are almost always setup to be a three in one light, moisture, and pH test kit. A light meter without a digital readout is essentially worthless and if you want to know if your soil is moist you can touch it. So the other two meters are just a value add gimmick that functionally produce little additional information.
If you do find a good reputable meter to purchase there are a few other disadvantages that come with these, though they are minor. Soil has to be moist to wet for these to work. While this is not a huge setback there are times where you’re not going to want to moisten a whole bed to test the soil, only to find you need to adjust it afterwards. Finally, and not really a hassle for us, waiting 10 to 15 minutes for a reading takes a while if you need to test many beds and lots of different soils.
Our Recommendations on Probe Based Soil pH Meters
If you don’t want to mess around with cheap meters that may or may not work, you’ll want to get something that is long lasting and durable. We recommend the Gain Express Soil pH and Moisture Meter as out number one pick. These are analog and require no batteries and these meters last for years. We’ve heard few complaints from other users that were not just people using them incorrectly. While we like this pH meter, it’s expensive running about $60 on amazon at the time of our writing. Compared to the other meters you might see it’s nearly 3 to 6 times as expensive, but those cheaper meters work maybe half the time. This is the obvious choice if you you’re not interested in wasting your time on a gamble.
If you want something a little less expensive, but still relatively good, you can use the Luster Leaf Rapitest Soil pH Meter. This product runs between $20 and $30 and is decently reliable. The readings are not quite as accurate and the meter is not as durable, but if cared for properly you can get a lot of value out of this garden tool.
pH Test Strips for Garden Soil
How to Use pH Test Strips for Soil
Test strips are simple sheets of paper soaked with a color changing indicator that shifts colors based on the pH of the moist material it is added to. To use these on soil simply take a representative sample of the soil, mix with an equal part water and let it sit for around 20 minutes and then dunk the pH strip in the solution after giving it one final mix. In about 10 seconds the color on the strip will change and you can compare to the testing chart to get the final pH.
Advantages and Disadvantages of Soil pH Strips
What we like best about soil pH strips is their consistency. They work well 100% of the time because they are an incredibly low tech solution. Beyond this they are cheap, portable, and leave minimal mess.
On the other hand, pH strips are a consumable and produce a small amount of waste. You’ll need to buy more every year or so, and if you somehow get the container they’re in wet or leave them open to moist air, you’ll have ruined the whole lot of them.
On a practical note, pH strips are very difficult for people with certain types of colorblindness to use. beyond this the color is dependent on the type of chemical reaction taking place so different strips may look different. If you loose your color chart for these you’re also out of luck (something we’ve done in the past).
Our Recommendations on pH Test Strips for Soil
We recommend Garden Tutor soil pH Strips if you decide to go this route. They are cheap ranging from $10-$20 and plentiful. While they’re not the best test strips on the market, for their price they are reliable and consistent. What’s also important here is that these are designed for testing soil. You will find a billion reviews online with people using them to test water, which is not what they are designed to do. Reading pure water will often show slightly more acidic than it actually is. To be honest these are not fool proof and different chemicals in your soil or water may cause the various indicators to read less than true, but for the most part you should be able to get a decent reading that will give you the information you need without much hassle.
DIY Soil pH Testing
Note: we’ve included this because people online are trying this or claiming it’s good enough. It isn’t. This method is far from accurate, and doesn’t give you helpful information for almost any edible plant that would require pH testing your soil. If you’re growing tomatoes and you need the soil pH to be just right, this method yields no usable results.
How to DIY Test Your Soil pH
For this method you start just like you would with a pH strip kit by mixing a representative sample of soil with equal parts water and letting it sit for 20ish minutes. Then, stir up the soil once again and sprinkle a very small amount of baking soda across the surface of your sample. If the baking soda bubbles your soil is acidic.
“Advantages” and Disadvantages of DIY Soil pH testing
This method only tells you if your soil is acidic, but it is full of holes. Baking soda is not very sensitive and reacts with almost any amount of acid. It may even bubble lightly if your water is a touch acidic… All that being said we really think this method is a waste of time. Don’t do this in anything but the most dire of circumstances and even still only use it if you need to know if your soil is basic vs acidic.
Test Your Soil pH
We cannot stress enough the importance of proper soil pH. In most situations it’s not a problem, but when it is a problem it can be very frustrating to troubleshoot. Testing your soil pH at the start of the year can help take a burden off your shoulders later and prevent you from making some rather silly mistakes with your crops. While there are a lot of plants you can grow in just about any soil, there are a handful of plants out there that need very specific conditions and understanding these needs along with the general readings of your soil will help give you a huge leg up over the course of the season. So get out there and do some garden chemistry!