Why do we need to feed our plants?

A letter sent in from one of the readers ran thus:

I seem to spend my life scattering things around my garden (chicken pellets one year, blood fish and bone the next, together with the contents, as far as it will stretch, of the compost bin), while acquiring a shed full of bags of partly used fertilisers because, we are told, different plants need different fertilisers.  But what am I actually achieving?  Is it all a plot on the part of the marketing people? could you explain simply what we need to do - and what you do, for instance?

To which Helen replied:

Oh what a loaded question!  Answering this has the potential to upset just about everyone - from white-coated scientists and the makes of Day-Glo inorganic soluble feeds right through to serried ranks of organic allotmenters.

In theory, we shouldn't need to feed our plants.  After all, the natural world looks after itself.  

A garden, however, is an unnatural environment.  We cram a small patch of earth full of plants that in their natural habitat might have very differing needs, and expect super performance year after year: fabulous flowers from roses, huge leaves from hostas, endless flowering from annuals, a perfect lawn ...  

Plants crowded together suffer from drought, which encourages disease, weakening them further.  To make things worse, we clear up every bits of debris from our gardens that would otherwise go back into the soil, eventually to create vital humus without which plants can't grow.  So we need first and foremost to feed the soil, putting back as much moisture-retaining, humus-creating organic stuff as we can - invariably more than those of us with average-sized gardens can make in our compost bin.


Whatever we choose or don't choose to do, we should all feed our plants. Certain plants will perform better - and importantly show more disease resistance - given certain nutrients, each of which has a different 'function': flowering plants (and tomatoes) like extra potash, summer lawns benefit from nitrogen that encourages green leaves, while the roots of autumn grass are strengthened by phosphates etc. And lime-haters don't like animal manure.

It is a big subject if you want it to be.  I try to keep it simple.

I give my garden masses of manure-based organic matter each year (which I buy, to supplment my own compost), adding it to the soil when I plant, and mulching around individual plants in spring.  I make oak-leaf mould for lime-haters and woodlands.  

In addition I spread a general, balanced fertiliser on my flower borders once a year (for 'balanced' nutrients look at the NPK ratio on the packaging - beware, you won't find precise information on chicken manure pellets, which are nitrogen-rich).  

I also give high potash rose food to my flowering shrubs and I use seaweed-based liquid fertiliser as a pick-me-up (for ailing plants, that is, not me, silly).

From an article by Helen Yemm in the Telegraph Gardening section



Time Lapse: Watching Flowers Grow  (http://www.youtube.com/watch?v=rQYjZRuAay0).  Remember watching the beginning of 'Watch with Mother'? (http://www.youtube.com/watch?v=qE9dsOu3oE8)