When we are thinking about planting seeds and plants out on the allotment plot, we first prepare our soil, adding compost, manure and other organic matter to improve it and provide more nutrients for a better crop. The more experienced grower will tend to know what type of soil they have and depending on the soil type will depend on what is needed to treat it and for which crop. But it does not mean it is a minefield!
There are six main soil types in the UK:
Clay
Sandy
Silty
Peaty
Chalky
Loamy
So, how do you know, which soil type you are likely to have?
Wet Clay soil is very sticky and lumpy
When clay soil is dry it is rock hard
Clay soil poorly drains
Fewer air pockets
Slower to warm up in Spring
Cultivation is heavy going
Holds more nutrients than other soils and therefore will produce good crops if the clay soil drainage is improved
Frosts and cold winters help dug over soil breakdown and before planting in Spring, ensure your planting area is broken down further directly around the plant with no gaps for waterlogging. It is advisable to work in some good compost and mulch the beds too.
Sandy soil is freely draining
It feels gritty
Quicker to warm up in Spring
Easy to cultivate
Dries out quickly
It can lack nutrients with this free-draining soil, quick drying soil.
Sandy soil will require a lot of regular watering and feeding but can produce a good crop with some TLC. Add generous amounts of compost and organic matter regularly and your soil may even need watering during dry spells in the winter.
Silty soil is smooth and soapy to handle
Holds moisture well
Richer in nutrients
Easier to cultivate than clay but is
Heavier than sand
Soil structure is easily compacted and is weak
A very good soil if well managed
Silty soil is very fertile and will require less help from other added nutrients from compost but that's not to say you can still treat it for your crops.
Peaty soil contains a much higher level of organic matter/peat because the soil’s acidic manner limits decomposition
Fewer nutrients
The colour is darker
Warms up quicker in Spring
Holds water and will require drainage
Fantastic for plant growth if fertiliser is added
Drainage such as peat moss can help retain the water along with other organic matter for nutrients. Peat moss alone will not aide your soil very well. Peaty soil is not commonly found in gardens.
Chalky soil is alkaline, with a pH of 7.5 or more
Very stony
Free draining, becoming very dry quickly
Often over chalk or limestone rock
This means some minerals, such as manganese and iron become unavailable to plants, causing poor growth and yellowing of leaves
This can be cured by adding fertilisers
Chalky soil can be treated with organic matter to improve the humus levels and moisture, on a very regular basis. Green manure will help provide nitrogen for vegetable growing.
Loamy soil is the most ideal soil!
Good structure
Drains well
Retains moisture
Full of nutrients
Easy to cultivate
Warms up quickly in spring and doesn’t dry out in summer
If you find that you have loamy soil, you have struck gold as a grower! To achieve this great balance if you have other soils, is to keep adding the compost and organic matter as well as mulching methods.
Shallow rooted vegetables such as lettuce, beans, chard, sprouts and cabbages like clay soil.
Carrots, potatoes, cucumbers and radishes like sandy soil.
Most fruit and vegetables will grow well in silty soil.
Brassicas, legumes, salad crops and root vegetables do well in peaty soil.
Spinach, beetroot, sweetcorn, cabbage and grape vines will grow well in chalky soil.
Most crops will grow well in loamy soil.
In summary and as common sense prevails, a good soil will provide a good balance of water retention and drainage, air flow and nutrients to grow a good crop with added help with the right compounds if, and when it is required.
Have you seen our Composting page?