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 Bluetooth 8-in-1 soil tester reads pH, EC, temperature, humidity, light, moisture, fertility, and salinity, and sends it all to a free app over Bluetooth. It is for gardeners who...

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...

A plant in a poorly lit location may continue to struggle even when watering and soil conditions are corrected, and light is one of the causes people check last. This...