Most of us green thumbs know exactly what our precious plants need for optimum growth. But how can you tell if your garden really has what your plants want?
Simple. Just test your soil!
There’s only one little problem. There are so many soil test kits out there. How are you supposed to pick the best one?
Read on to get all your soil testing questions answered. We’ll give you everything you need to know about sampling your soil and getting it tested.
We’ll also give you a run-down on some of the best soil testing kits available on the market.
Here are some quick options if you don’t have time to read the whole article.
Our Top 4 Home Soil Testing Kits
Let’s take an in-depth look at some of the best soil testing kits for home gardens and what makes them so popular.
We’ll look at the best soil testing kit for each soil testing type, as well as the best budget option.
1. Luster Leaf 1601 Rapitest – Best Chemical Test
- Chemical soil test kit
- Tests for N, P, K, and pH
If you need a quick but reliable overall soil test at home, this is one of the best there is. Luster Leaf is one of the most popular gardening brands and is known for its dependable quality.
This testing kit is very easy to use, even for novice gardeners. It’s also quite accurate, and you’ll have your results in mere minutes!
It does take a steady hand to measure out the liquid, but that’s a small price to pay for a good NPK reading.
- 40 tests, 10 each for N, P, K, and pH
- Easy-to-use setup, even for beginners
- Comes with soil pH preference list for 450+ plants
- Some people found it difficult to perform the phosphate test.
2. Atree 3-in-1 Soil Meter – Best Analog Test
- Analog soil test
- Tests for pH, moisture, and light
No batteries, no measuring, no color coding schemes. This simple yet robust analog testing meter from Atree will work for you every time you need it to.
This meter may seem a little pricey, but it has Atree’s hallmark robust build. It is made to last, and you won’t be buying a new one for several springs to come.
Easy to use, this meter will give you the readings you need in 10 minutes. And it’s hassle-free. You only need to clean the probes after every use.
The only downside is that it can’t measure your soil’s NPK content.
- Easy to use
- Very accurate for an analog meter
- Unlimited number of uses
- A few users received a faulty meter.
3. Luster Leaf 1847 – Best Digital Test
- Digital Test
- Tests for pH
Luster Leaf has every possible soil testing kit you might need, whatever the occasion. And the brand is popular because people know they’re buying reasonably priced, quality items.
The Luster Leaf 1847 is a purely digital test kit designed to give you an accurate read on your soil pH. The reading is instantaneous, and all you need to do is clean the probe before moving on to the next sample spot.
So no matter how big your garden or lawn patch, you can test it all over for pH in a matter of minutes.
If you need fast, accurate pH readings and moisture is not a priority, this is the way to go.
- Detachable probe lets you get to plant root level
- Instant pH reading
- Operated by a single AAA battery
- LCD could be clearer.
4. iPower LGTESTSOIL – Best Budget Option
- Analog Test Kit
- Tests for pH, moisture, and light
This handy, compact little analog meter is a great option if you don’t want to pay a fortune.
Perhaps not as accurate as comparable models from Luster Leaf, this iPower will still give you reasonably good readings. It is also incredibly easy to use.
You might raise your eyebrows at iPower as it is a lesser-known brand. The instruction manual is clearly written by a non-native speaker.
But they cover this LGTESTSOIL meter with a 12-month warranty, and using it is really not rocket science. Keeping in mind the low price point, what’s not to like?
- Very affordable
- Easy to use
- No limit on the number of uses
- Light and portable
- 12 months warranty
- Low sensitivity so it takes a bit of time to get the readings.
Why Should You Test Your Soil?
Plants, just like animals, need good nutrition to grow well. But except for sunlight, most plants get everything they need from the soil they’re growing in.
From macronutrients like Nitrogen, Phosphorus, and Potassium (that’s the NPK label you see on fertilizer boxes), to micronutrients like Zinc and Calcium, there’s a lot plants need to stay healthy.
How acidic or alkaline your soil is also matters, and is referred to as soil pH. Most plants like neutral soils with a pH of 6.0-7.0, but some prefer more acidic soils.
And just like us, plants need water to survive. How much they need to thrive differs from plant to plant, so keeping your soil at the right moisture levels is also important.
Test your soil before you start your garden
It may seem like a hassle, but it pays to test your soil before you actually plant your stuff, whether it’s veggies or flowers.
Testing is the only way to figure out just what you’re working with. Once you know what you have, you’ll know what to do to turn it into what you need.
If you’re lucky, you may not need to do anything at all. Just dig in (quite literally!) and get planting.
But if you find your soil is less than perfect, you can start figuring out what to blend it with to get the nutrient profile you want.
Don’t rush it with the fertilizer!
Everybody knows that fertilizing your soil is good for plants, right?
Raincheck!! There is such a thing as overfertilization, and it’s not a good idea. Too much is as bad as too little and can cause all sorts of funny growth patterns in your plants.
And again, the only way you’ll know if you need any fertilizer and what kind is by testing your soil.
What To Test Your Soil For
Okay. You know you’ve got to test your soil and all that. But what exactly are you testing it for?
Here you test to see how alkaline or acidic your soil is. The pH scale goes from 0-14, with 0 being the most acidic and 14 the most alkaline.
Most plants prefer a neutral-ish soil with a pH range of between 6 and 7.5, but some prefer more acidic environments.
Once you know your soil pH, you can adjust it if you need to. Products like lime and calcium can be used to raise or lower the pH of soil.
The three macronutrients are Nitrogen (N), Potassium (P), and Phosphorus (K).
Nitrogen is the primary ingredient used by plants for leaf and stem growth, but different plants require different amounts. What is just right for one plant may be too much for another, and the other way round.
Phosphorus encourages flower and fruit growth. Regardless of whether you have too little or too much, if the amount isn’t just right, you’ll be getting a poor harvest from crops like tomatoes and cucumbers.
Potassium is what your plants need to develop their root systems. Too little, and the under-developed roots may cause the whole plant to stunt. Too much, and root crops like carrots can end up badly misshapen.
These are just as important to plants as the macronutrients. The only real difference is that they are usually required in smaller quantities than NPK.
There are several micronutrients, including Molybdenum, Copper, Manganese, Calcium, and Zinc.
The one problem is that most soil testing kits aimed at the home gardener do not test for micronutrients. So the only option is to have your soil samples analyzed by a professional soil testing lab.
How to Take a Soil Sample
To get an accurate soil picture of your garden, you need to take several small samples, called cores, from various spots. Ideally, you need at least 10 cores.
- Use a stainless steel or plastic shovel and bucket to collect your soil, as other materials can contaminate the soil and skew your results.
- Dig down to the depth where most plants and grasses have their roots, and collect a small shovelful of soil.
- Once you have all your cores collected, blend them thoroughly in your bucket, and allow the soil to dry.
At this point, your soil is ready for testing, be it at home or a professional lab.
Soil Tester Types
Professional soil-testing labs aside, there are three types of soil testers available to hobby gardeners.
- Chemical soil testers are not complicated, but the number of uses is limited to the number of reagent vials or capsules that come with it.
The idea is simple. Put your soil sample in a vial, then top up with water, and add a colored capsule to match the color on the vial’s lid. Each soil nutrient is color-coded to avoid confusion.
Chemical soil testers won’t be as accurate as taking your sample to a lab, but the results are reasonable enough to work with in a home garden setting.
- Analog soil testers are simple to use and cheaper than chemical testers, but they’ll only test for soil pH and moisture. If you need to test for macronutrients, you’ll have to go for another option.
These devices have two or three metal probes that you place into the ground to get a reading on pH, moisture, and sometimes sunlight. The results are far from the most accurate, but for a quick soil test, it’s enough.
- Digital soil testers are more accurate than their analog counterparts, but a little more finicky too. They are battery-operated, and you have to thoroughly clean the probes before every use to get a correct reading.
Just like the analog ones, these will generally test only for soil pH and moisture. So again, if you need to test for macronutrients, go for a chemical tester, or send your samples to a lab.
Professional Soil Testing (Possibly for Free!)
Most areas of the US and elsewhere will have a professional soil-testing lab available. It may be at an educational institution, the government agric extension office, or a private company.
Professional soil analysis doesn’t come cheap, but sometimes you can get a subsidized rate.
Agricultural colleges and government agricultural extension services often offer subsidized soil testing services. Sometimes, you can even get them completely free!
So ask around your local area to find out what options are available to you.
Soil testing is the only way to know if your soil has what your plants need to stay happy.
Professional soil testing at a lab is certainly the most accurate and reliable option, but it’s also the most expensive. And you’ll have to wait a while to get your results back,
A much quicker and cheaper option is to acquire a simple soil testing kit and do the job yourself. The results may not be as accurate as those from a lab, but they’re more than enough to give you a good idea of the basics.
Chemical, analog and digital testing kits each have their perks. Take a look at our top 4 for the pros and cons and the best of each.