6 Soil Organic Matter Test Kits That Prevent Common Issues

You’ve done everything right—good seeds, proper spacing, and timely watering—but your crops just seem… stuck. The tomatoes are small, the squash vines are lackluster, and the beans look pale. The problem often isn’t what you’re doing above ground; it’s what you’re missing below it.

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Why Soil Organic Matter is Crucial for Your Farm

Soil organic matter (SOM) is the dark, rich, living portion of your soil. It’s the decomposed remains of plants and animals, and it’s the engine of a healthy farm. Think of it as a sponge, a pantry, and a high-rise apartment building all in one. High SOM levels mean your soil holds more water, which saves you time and effort during dry spells.

This spongy structure also creates air pockets, preventing compaction and making it easier for roots to grow. More importantly, SOM is the pantry where plant nutrients are stored and made available. Microbes in the soil break down organic matter, slowly releasing nitrogen, phosphorus, and other essentials exactly when your plants need them.

Without enough organic matter, your soil is just mineral dust. It can’t hold water, it compacts easily, and any fertilizer you add is more likely to wash away than feed your crops. Building SOM is the single most important investment you can make for long-term productivity and resilience on your hobby farm. It’s the foundation for everything else you hope to achieve.

MySoil Test Kit: Simple Mail-In Lab Analysis

If you want a reliable number without the fuss, the MySoil Test Kit is a great starting point. It’s designed for simplicity. You take a sample using their included tools, pop it in the mail, and get your results back through an online dashboard. It’s clean, fast, and removes the guesswork.

The kit provides your SOM percentage alongside key nutrient levels like nitrogen, phosphorus, and potassium (NPK), plus pH. This is a huge advantage over basic pH strips. You get a clear, actionable number that tells you where you stand.

The tradeoff is a lack of deeper detail. You get the "what" but not necessarily the "why." For a hobby farmer just starting to test their soil or wanting a quick annual check-up on a specific garden bed, this is an excellent, low-effort choice. It gives you the core data you need to decide whether to add more compost or change your cover crop strategy.

Soil Savvy: Nutrient and SOM Data Combined

Soil Savvy operates on a similar mail-in lab model but presents itself as a more comprehensive diagnostic tool. It provides a single, easy-to-read report that shows your SOM alongside a wider array of macro and micronutrients. This is ideal when you suspect a specific deficiency is holding your crops back.

Imagine your peppers are showing yellow leaves, but you’ve already added a balanced fertilizer. A Soil Savvy test might reveal that your SOM is decent, but you’re critically low on magnesium or sulfur. By combining the SOM data with a broader nutrient profile, you can make much more targeted amendments instead of just guessing with more compost.

This kit is perfect for the farmer who has moved beyond the basics and wants to understand the interplay between organic matter and nutrient availability. It helps you answer more complex questions. It’s less of a simple check-up and more of a diagnostic consultation, providing a clearer path to fixing specific, nagging issues in your garden or pasture.

LaMotte STH-14 Kit for Hands-On Humus Testing

For those who prefer a hands-on approach and want immediate feedback, the LaMotte STH-14 is a classic. This isn’t a mail-in service; it’s a field kit with test tubes, reagents, and color charts. It allows you to perform multiple tests for a range of nutrients, pH, and—most importantly—humus, the stable, long-lasting component of soil organic matter.

The big advantage here is speed and frequency. You can test your compost pile as it matures, check a new bed before planting, or compare different parts of your property on the same afternoon. This iterative testing helps you develop an intuitive feel for how your management practices are affecting your soil in near real-time.

However, precision is the tradeoff. These colorimetric tests are less exact than a lab analysis. They are best for spotting trends and making directional decisions—is this soil better or worse than it was last season? If you enjoy the science and want to be more deeply involved in the process, this kit is an empowering tool that puts the lab right in your hands.

Waypoint Analytical for Professional-Grade Data

When you need definitive, no-nonsense data, you send your sample to a professional lab like Waypoint Analytical. This isn’t a "kit" in a box but a professional service used by full-time farmers, and it’s completely accessible to hobbyists. You simply mail your soil sample with a submission form, and they email you a detailed report.

This is the right choice when the stakes are high. Perhaps you’re trying to restore a seriously depleted pasture or you’re preparing a large plot for a high-value crop like garlic or lavender. The data you get back is incredibly precise and includes SOM, a full nutrient panel, cation exchange capacity (CEC), and pH.

The report can be intimidating at first, as it’s packed with information. But for the serious hobby farmer, this level of detail is invaluable. It removes all doubt and provides a solid, scientific baseline for your soil management plan. It costs more than a simple kit, but the accuracy can save you hundreds of dollars in wasted amendments and lost crops.

Earthfort Analysis: A Focus on Soil Biology

If you see your soil as a living ecosystem, then Earthfort is the lab for you. They go beyond the basic chemistry to analyze the biology of your soil. An Earthfort test will tell you about your soil’s bacterial and fungal biomass, identify protozoa, and even count beneficial nematodes. This is a fundamentally different approach.

Why does this matter? Because a soil can have decent organic matter but be biologically dead. Without a thriving microbial community, nutrients remain locked up and unavailable to plants. This test is perfect for farmers practicing no-till, using complex cover crop mixes, or brewing their own compost teas. It helps you understand if your efforts to build a living soil are actually working.

The results from Earthfort require a shift in thinking. Instead of just adding nutrients, you’ll be focused on adding foods for your soil life—things like fish hydrolysate or diverse organic matter. It’s the ultimate tool for diagnosing the health of your soil’s microbiome, not just its chemical composition.

Logan Labs Standard Test for In-Depth Analysis

Logan Labs is another top-tier professional laboratory that has become a favorite among knowledgeable growers. Their Standard Soil Test provides a fantastic balance of depth and value. It gives you a precise SOM reading alongside a comprehensive look at your soil’s chemistry, including base saturation percentages and trace minerals.

This test is for the data-driven hobby farmer who wants to understand the "why" behind the numbers. For example, knowing your base saturation of calcium, magnesium, and potassium helps you balance these competing nutrients for optimal uptake. It’s the difference between just adding lime to raise pH and adding the right kind of lime (calcific or dolomitic) to also correct a mineral imbalance.

While the report is dense, it’s a goldmine of information for anyone willing to learn how to read it. Logan Labs empowers you to move from generic advice to a highly customized fertility program. It’s the test you get when you’re ready to stop guessing and start managing your soil with precision.

Interpreting Your SOM Results for Better Crops

Getting a number back is one thing; knowing what to do with it is another. Your SOM percentage is a guide that tells you what your next steps should be. It’s not about hitting a "perfect" number, but about understanding your soil’s current capacity and potential.

A low result, say 1-2%, is a clear signal to get aggressive with building soil. This is not the time for small tweaks. Your primary focus should be on:

• Heavy compost applications: Add at least an inch of well-rotted compost annually.
• Intensive cover cropping: Use mixes with deep-rooted plants like daikon radish and heavy biomass producers like sorghum-sudangrass.
• Mulching everything: Never leave soil bare. Use wood chips, straw, or grass clippings to protect the soil surface and feed soil life.

If your results are in the 3-5% range, you’re in a great spot. Your job is now maintenance and gradual improvement. Focus on smart crop rotations that alternate heavy feeders (like corn) with soil builders (like beans). Continue with annual compost applications, but you can be more targeted. This is the stage where you’re sustaining a healthy, productive system.

A high result of 6% or more is fantastic, but it brings new considerations. At this level, your soil has an incredible ability to hold water and nutrients. Your focus shifts from building to balancing. Very high SOM can sometimes tie up micronutrients, so ensure your testing includes minerals like zinc and copper. The goal is to keep the biological engine running smoothly without creating new imbalances.

Ultimately, testing your soil organic matter isn’t an expense; it’s an investment in information. It replaces guesswork with a clear strategy, helping you build your farm’s most critical asset—healthy, living soil. Choose the right test for your goals, and you’ll be on your way to better crops and fewer problems.