The importance of fertiliser
JUST like an animal waking up from hibernation your garden is also waking up and just like an animal it is waking up hungry. Despite the dishwater skies of late a close inspection of your garden will show the daily advance of fresh buds springing open no less.
Plants are very adaptable and may well perform and survive through years of negelect but if you do only one thing in the garden this year, and I would suggest every year, it is to apply a general fertiliser. As with most aspects of horticulture plant nutrition, if you study it in depth, becomes a science. Here well try to keep it simple.
First up fertiliser is not the same as bulky organic matter, ie. farmyard manure, garden compost and leaf mould. These materials not only contain nutrients but also are invaluable as soil conditioners.
Bark mulches also break down and supply organic matter but should be used as mulches only and not incorporated into the soil as the others can be.
Bulky organic matter and mulches encourage worm activity, high humus levels, healthy soil bacteria and a health soil structure which helps to create a friable soil. Nothing to do with cooking but refers to that lovely crumble soil we all crave.
Creating a friable soil enables your soil to hold on to nutrients better and prevent leaching. Leaching is a term that refers to nutrients being lost from the soil by rain water, something we known a lot about here in Ireland.
Mulching every couple of years with these materials is even better than just fertilising but as the very word bulky suggests it can require rather more effort to apply than some are willing to put in. The application of a fertiliser is so simple no one should have an excuse. But for the best results mulch every couple of years and fertilise every year.
Plants top nutrient requirements are nitrogen refered to as N on fertiliser packets, phosphorus seen as P and potassium K . In very simple terms this equates to N = growth, P = roots, K = flowers and fruit. Hence grass fertilisers tend to have a high nitrogen rating where as rose and tomato feed tends to be high in potassium. Below these in requirement come calcium, magnesium and sulphur. Further down the list are what is refered to as trace elements which are required in tiny amounts.
In most garden soils the N,P,K are all you have to worry about. A good general garden fertiliser will have a balanced ratio of 5:5:5 NPK plus your micronutrients.
There are four methods of applying fertiliser. Top dressing, which is the application to the soil surface. Base dressing which is incorporating as you plant. Watering on is liquid feeding the roots system. Foliar feeding which is applied to and taken in by the leaves. There are two types of fertiliser in all these categories, organic which are derived from animals and plants and inorganic which are man made.
For existing plants borders apply a general fast release fertiliser like growmore from early April. This will usually provide three months of feed. Another application at the end of June is recommended. If base dressing, particularly in winter use a slow release or controlled fertiliser. Blood , fish and bone will do this and should feed for six months. Liquid feeds for both roots and foliage are fast acting and short term. Applications for these need to be done every two weeks during the growing season.
Always read the manufacturers instructions and wear gloves when handling the product. For best advice as always pay a visit to you local garden centre.