This soil tester from St Helens Home and Garden combines a moisture meter, PH acidity tester and light sensor. This will help you to understand when to water your plants, adjust the PH levels and if your plants are getting adequate sunlight. Simply insert the sensor probe into the soil you wish to test and the sensor gives you a comprehensive and accurate picture about the soil condition of your garden or lawn. Plants that grow in the optimum moisture, PH and light environments grow stronger and quicker than other plants. The sensor is compact and does not require batteries or any other power source to work. This handy little item is a must have for gardeners and can be used for testing the soil in garden borders, lawns, pot plants and hanging baskets.