Gardman pH Meter
From thegardensuperstore.co.uk: "The Gardman Soil pH Meter is a very easy to use meter that tests the soil for acidity and alkalinity for optimum planting and crop care. This meter can be used many times over and does not require any maintenance or batteries. "Soil pH is extremely important and can decide on what crops can be gown or why some plants seem to thrive, whilst others do not do well. Once a soil pH has been ascertained, it can be adjusted, if necessary, whereby to reduce acidity limestone is added to the soil, whereas to increase acidity Sulphate of Ammonia is added. Vegetable plots that have been heavily worked over the years are well worth checking as the soil tends to get acid over time. For those wishing to plant acid loving plants, such as Azaleas and Camellias, it is well worth using a pH Meter to check that the soil is suitable before purchasing and planting."