Type of fertiliser

 

Organic fertilisers tend to be slower acting and have organic origins. They include seaweed, hoof & horn, dried blood, fish blood & bone, bone meal, poultry manure pellets and liquid comfrey or nettle feeds.

 

Fertilisers can be bought that include a mixture of N, P and K these are referred to as compound fertilisers. Straight fertilisers are based on one major nutrient and are usually inorganic. Control release fertilisers also are usually inorganic; these release nutrients gradually into the soil over a period controlled by a porous coating. Slow release fertilisers are usually organic and gradually broken down by soil organisms.

 

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If you grow comfrey you can make your own comfrey tea.

 

Just use a container large enough to hold the amount of comfrey and cover it with water. Leave it for about 3 weeks and then strain off the liquid. Dilute it 10 parts water to 1 of comfrey juice and use a a general plant feed. Beware it does smell foul!

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How to apply fertiliser

 

Different fertilisers require different methods of application and you should always follow the instructions on labels.

 

They may be sprinkled on the soil surface usually in spring. This is called top dressing. Care should be taken not to get fertiliser on plant leaves as they could burn. Too much fertiliser applied this way can also damage roots so carefully read the application guidance.

 

Fertiliser can be incorporated in soil or compost before planting; this is called base dressing.

 

Liquid or soluble powered fertilisers can be watered onto plant roots. Again care should be taken not to splash leaves. These fertilisers tend to be used for container or greenhouse grown plants.

 

Some fertilisers can be applied by direct spraying or watering onto leaves. This is called foliar feeding and should not be carried out during sunny periods as the leaves may be scorched. Spray applied to young leaves and the undersides of leaves is particularly effective.

 

What else is needed to improve the soil?

 

Soil also needs to have a good structure or texture, it shouldn’t be too cloggy or it can become waterlogged but neither should it be too sandy as water will quickly drain through leaving the top layer arid. The aim is for a crumbly soil containing air pockets. Soil conditioners are used to improve the soil structure. Conditioners include homemade compost, spent grow bags, mushroom compost, straw and manure. (Read this before acquiring manure). Some soil conditions such as mushroom compost can alter the PH of the soil.

 

You may also like to learn about our experiences with green manures click here for more.

 

Testing the soil

 

The PH of soil is also important. The PH indicates whether the soil is alkaline or acidic. A PH of around 7.0 indicates that the soil is neutral i.e. neither alkaline nor acidic.

 

A PH level of 6.5 is considered the best level for most plants. Soil testing kits to check the PH level are available.

If the soil PH is too low garden lime can be added. It is important that garden lime and not builders’ lime is used. There are also applications containing sulphur and iron sulphate available to lower the PH if the soil is too alkaline.

 

Some plants grow better in soil that is acidic or alkaline so you should read up on your plants requirements before purchasing.

 

Kits are available to enable you to check the PH level of soil but bear in mind that this may vary in different parts of your plot or garden so you need to test in various location.

 

Some kits will also test the N, P and K levels in the soil.

 

Some tests use a probe but from what I have been told by other gardeners (I have to admit to never testing our soil) these may not be as reliable as those which use a liquid formula.

 

 

Photos taken from

Gardening Naturally

,

Harrod Horticultural

and

Greenfingers