An NPK soil tester reads the three nutrients plants need most—nitrogen (N), phosphorus (P), and potassium (K)—plus soil temperature. This one gives you those readings in seconds from a dual-needle...

This 8-in-1 soil tester for plants reads pH, moisture, EC, temperature, light, and an NPK estimate, and sends the data to your phone. Unlike USB-only probes, it works with both...

This rechargeable soil nutrient tester reads one main nutrient—nitrogen, phosphorus, or potassium, depending on the version you choose—on a large backlit screen, and charges over USB-C, so there are no...