Good gardening begins not with guesswork, but with knowing the ground beneath your feet. Here you’ll find simple diagnostic tools to measure soil pH, nutrient levels, moisture, and temperature, along with compost thermometers and other monitors that reveal what the soil is actually doing. These instruments help you decide when to fertilize, when to amend, and when to leave well enough alone — guiding healthier roots, stronger growth, and wiser use of time and materials.