Your soil

It is important to understand your soil, how to improve it and which plants natually enjoy it's properties. Soil is basically a mixture of organic matter, rock, mineral particles, air, water and nutrients. Different plants like these in different combinations.

Read through these descriptions, and make a note of what soil type, pH and moisture you have. At the end of each of these overviews there is a check you can do while handling the soil. Once you have read them all, we will ask you to go outside to make some tests in your garden. If you have a registered account, you can record the answers. With this stored information, we can then provide better advice to you.

1. Soil Type - what type of soil do you have?

The main soil types are:

Loam - often seen as the ultimate garden soil because most plants will grow in it, this is brown and crumbly in texture and similar to that found on well-worked allotments. It's rarely waterlogged in winter or dry in summer and supports a wide range of plants. Loamy soil is light and easy to dig and is naturally high in nutrients.

Take a handfull of soil and squeeze it in your hand. If it has a smooth, rich texture and it slowly looses its shape, then it is probably loam based.

Things to check:

• Drains well
• Retains moisture
• Easy to cultivate
• Warms up quickly in spring and doesn't dry out in summer

Chalk - chalky soil is very shallow, full of clumps of white chalk or flint and is very free-draining. This means it can be bone dry in summer and plants will need far more watering and feeding than on any other soil. Chalky soils are always alkaline, which restricts the number of plants that can grow on them. Planting may also be difficult as spades frequently hit lumps of hard chalk or flint. Some minerals, such as manganese (Mg) and iron (Fe), may also become unavailable to plants, causing poor growth and yellowing of leaves. However, this can be remedied by adding fertilisers.

Take a handfull of soil and squeeze it in your hand. If it has a greyish colour and white gritty chunks in it, then it is probably chalk based.

Things to check:

• Usually stony
• Free draining
• Often overlays chalk or limestone bedrock

Clay - Clay soil is naturally high in nutrients so plants that like these conditions should do particularly well. It does pose some problems too however. In summer, it is often baked dry, with visible surface cracks, making it difficult to get water to plant roots. It doesn't allow much air to penetrate so in winter, it can be constantly wet and waterlogging is common. It is hard to dig at most times of the year, and only warms slowly in the spring. If drainage is improved, however, plants grow well as it holds more nutrients than many other soils.

Take a handfull of soil and squeeze it in your hand. If it is slimy and sticky and the lump hold its shape, then it is probably clay based.

Things to check:

• Feels lumpy and sticky when very wet
• Can be easily rolled into a ball shape
• Rock-hard when dry
• Clay drains poorly
• Hard to dig over

Sand - feels rough and gritty when handled and will not form distinct shapes like clay. It usually has a sandy brown colour and is easy to dig over. Water-logging is rare on such soils as they are very free-draining and, accordingly, watering and feeding of plants is needed on a regular basis. It is quick to warm up in the spring, so sowing and planting can be done earlier in the year than with clay or silty soil. May lack nutrients, which are easily washed through the soil in wet weather (often called a "hungry" soil.)

Take a handfull of soil and squeeze it in your hand. If it is gritty and the lump you made crumbles, then it is probably sand based.

Thing to check:

• Free-draining soil
• Gritty to the touch
• Warms up quickly in spring
• Easy to cultivate
• Dries out rapidly

2. Soil pH - what is the acidity in your soil?

The pH of a soil refers to its acidity or alkalinity and is a vital factor in plant growth. It is easy to measure and is usually listed numerically on a scale of one to 14. Acid soils have a pH of below seven, neutral is pH7 and alkaline is above seven.

For most garden plants a neutral soil is ideal but some, such as rhododendrons and camellias, must have an acid soil. Others, including many clematis and lilacs, prefer alkaline conditions.

The majority of amateur soil testing kits are very simple and rely on colour rather than a numerical scale. Acid soils turn a solution yellow-orange, neutral turn it green and alkaline, dark green.

You can also take a guess at your soil's ph. If you have soft water in your area, then it is mostil likely acid soil. If you have hard water (a telltale sign is 'scum' around the bath once you've drained it) then you probably have alkaline soil.

3. Soil Moisture - Do you have well-drained, waterlogged, or moisture retentive soils?

Perhaps you have a few different types of soil drainage in your garden, and even a pond which of course can tolerate plants which grow completely submerged in water. Check which of these soil drainage situations you have and then add to the details in your personal garden account. Like all the information you provide, this will help us provide better advice to you.

Another simple test you can do yourself is to water an open area of soil with a watering can. If the water disappears quickly, you have sandy, free-draining soil. If it stays on the surface for a long time it is more likely to be moist, and water retentive.

Here is a handy document to print out so you can take it out to the garden to test your soil. Click to download