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Soil types and how to improve them

What is good soil?

Good soil is well drained yet holds a moderate amount of water.  It is rich in nutrients, crumbly in structure and neutral in pH balance i.e. 6.5 - 7.  Healthy soils will have a good population of earthworms.

Why do we need good soil?

A well-conditioned soil ensures that you will get the best results. Tasty good-looking fruit and vegetable in abundance, masses of flowers and a healthy green lawn.  Whatever the condition of your soil you can improve it with a little effort by simply identifying the type of soil in your garden and treating it with the appropriate combination of fertiilisers and conditioners.

What is pH?

pH is a measure of the amount of free hydrogen ions in the soil on a scale of 0 to 14.  At the highest end (14) the soil is alkaline; at the lowest end (0) it is acid.  Certain plants such as Heathers, Rhododendrons, Azaleas, etc. cannot grow well in soil with a pH higher than 4.5 to 5.0, a level that would be unsuitable for vegetable crops and most flowers.  You can easily test the pH level in your garden soil with a do-it-yourself soil test kit.  If the reading is too low, say below 5.5 for the plants you wish to grow, then J. Arthur Bower's Garden Lime should be applied annually until the desired level is achieved.

Soil Types and How to Improve them


Peaty Soils

Possibly acid, with a pH reading of 4.0 to 5.5.  Suitable for growing heathers and other ericaceous plants.  Little else will thrive.

How to improve them

In the autumn dig plenty of bulky organic matter such as J. Arthur Bower's Mulch & Mix, J. Arthur Bower's Farm Manure, New Horizon Garden Compost or homemade garden compost into the top 40-45cm (12-18") of oil.  In spring apply J. Arthur Bower's Garden Lime liberally at the rate of 105-210g per sq metre (3-6oz per sq yd).  Repeat this process each year until the correct pH balance is reached, but you should notice a big improvement even after twelve months.

Light, Sandy Soils

Water drains rapidly through these soils, taking many of the nutrients with it.  the soils could well be acidic, in the region of 4.0 to 5.5.

How to improve them

 In the autumn dig in J. Arthur Bower's Extra Care Soil Improver for light and sandy soils.  Apply a 3cm mulch of New Horizon Mulch & Mix or Garden Compost.  This will protect against leaching effects of the weather and will break down to provide a better foundation for sowing and planting in spring.

In spring apply J. Arthur Bower's Garden Lime at a rate of 105-140g per sq m (3-4oz per sq yd) and apply some J. Arthur Bower's Fish, Blood & Bone or New Horizon Multi-Purpose Plant Food to remedy the nutrient shortage.  Mulch after planting with Mulch & Mix

For further handy tips see our information sheet "Working with Clay and Sandy Soils".

Light, Chalky Soils

 These have the same drainage and nutrient-leaching problems as light,sandy soils but the pH level, instead of being acid, will be slightly alkaline, reading between 6.5 to 8.0.

How to improve them

Treat the same as light, sandy soils except do not add any lime if the pH is over 7.5.  Dress the soil liberally with New Horizon Organic Garden Compost or New Horizon Mulch & Mix.  Alternatively use homemade garden compost.

Heavy, Clay Soils

Sticky, wet and heavy to dig in rainy weather, and rock hard in summer.  However, these soils are potentially very fertile.  They usually have a reasonable pH of 6.0 to 7.0,

How to improve them

Dig over roughly in the autumn and incorporate J. Arthur Bower's Extra Care Soil Improver for Heavy and Clay Soils.  Leave the clods exposed over the winter as frosts will then break them down.  In the spring you can fork it over prior to planting.  Apply Fish, Blood & Bone and then a layer of New Horizon Mulch & Mix.

For further handy tips see our information sheet "Working with Clay and Sandy Soils".

Stony Soils

Stones offer a clue to the soil type.  if your garden soil is quite thin, with more than its fair share of pebbles, the soil is probably slightly acid or neutral.  But if the stones are fragments of chalk or limestone, then your soil is undoubtedly alkaline.

How to improve them

For pebbly soil take the action indicated above for light, sandy soils.

If chalk or limestone fragments are present take the action for light, chalky soils.

In either case, attempts to riddle out stones are likely to be fruitless.  Concentrate instead on adding bulky matter such as J. Arthur Bower's Organic Garden Compost or homemade garden compost, which will eventually form a layer of rich humus over your stony soil

J Arthur Bower's New Horizon Dead Fast Growing Success