A guide to different soil types
Before you start growing anything in your garden you need to establish which soil type you have. Soil type, whether it is clay, sand, silt or loam, or acid or alkaline plays a crucial role in determining how well plants will grow in your garden or, most importantly, which plants will grow well there. To work out which type of soil you have it can help to look around at what's growing well in your neighbour's gardens as well as in the local environment, but bear in mind that each garden also has individual microclimates of shade, warmth and cold, so it is probable you wont be able to grow exactly the same plants in your own garden.
Once you know your soil type and the plants you can grow, gardening is so much more successful - and enjoyable, so if you don't know exactly what your soil type is, now is the time to find out.
Initially, the best way to tell which soil type you have is by feeling it. Clay soil feels sticky when wet and smears if you rub it between your fingers, while a sandy soil feels gritty and won't stay together. Different soil types can present their own particular problems, for example sandy soils don't hold water well and plants grown in it need lots of watering; clay soils on the other hand are prone to waterlogging and are no good for plants that need free draining conditions.
More crucially however, you need to establish which of the three different soil types you have - acid, alkaline or neutral. Soil type is measured by a pH number, on a scale from 1-14, with 7 being neutral, anything below it classed as acid and everything above it, alkaline and it's very easy to find out which you have by using one of the simple soil testing kits available to buy from garden centers. Simply mix a soil sample from your garden with a chemical solution from the pack and some rainwater and dip in the testing stick. The different pH levels are indicated by a colour and the colour your testing stick turns will determine which pH and therefore, which soil type yours is - yellow-orange is usually acid, green is neutral and dark blue alkaline.
Different soil types
The more extreme a soil type, at either end of the pH scale, the more difficult it is to garden, not just because it limits the range of plants you can grow but also because as a soil becomes more extreme, fewer nutrients become available, causing problems such as leaf chlorosis, when leaves lose their colour, or club root, a disease of acid soil.
In a very acid soil type, such as ones below a pH of 3.5, the few nutrients there are can be easily washed away by rain and watering, and phosphates, essential for plant growth, become unavailable to any plants that don't naturally come from that soil type. In the wild, acid peat moorland supports very few species and even the toughest acid loving plants, such as rhododendrons, cannot cope there.
However, as acidity decreases, soil becomes less tricky to deal with, until a pH of 6.5 is considered by many gardeners to be the ideal soil type, as you can grow the widest range of plants of all in it.
At the other end of the scale, extreme alkaline soil types, commonly referred to as chalky, are often poor, stony and very free draining, making them difficult to garden and a struggle to keep fertile.
Plants for different soil types
Many plants are unfussy about soil type, happy in acid, neutral, even alkaline conditions, while others will only thrive in a particular soil. Some plants actively need an acid soil type and are often described as ericaceous plants to indicate that they must have an acid soil to grow well. They include well known plants such as camellias, rhododendrons and azaleas but there are a surprising number of other plants happy to grow in an acid soil. Often coming from woodlands in the wild acid loving plants also frequently cope well with shade and cool, damp soil. At the opposite extreme alkaline plants are happy in chalky soils, which are often very shallow and free draining but can still support, if conditions are not too severe, a generous amount of plants.
Gardeners often think that having a particular soil type is problematic and limiting but once you know which soil type you have, you may well be surprised at just how many plants you can actually grow.