High soil acidity is usually caused by the breakdown of organic matter, so it's often found in woodland, due to the abundance of fallen leaves. For example, beech woodland has an average soil pH of 3.5-4.5.
You can test the pH of of your own soil using a soil testing kit (on a scale of 1 to 14, acid is between 1 and 7). If it's slightly acidic, you can grow a huge range of plants. But the more acidic the soil, the more limited your choice will be.
To find out how to keep ericaceous plants happy, check out our advice on how to garden on acid soil.
Browse our choice of plants that thrive on acid soil, below.
All magnolias will relish growing in acidic soil. The pink chalice-shaped flowers of Magnolia x veitchii open in early spring on bare branches. Young leaves are tinged purple, turning green as they mature. Grow it in moist but well-drained, neutral to acid soil, in sun or part shade.