Feeding your Crops

Feeding Your Crops:

All plants require three main nutrients for growth- nitrogen (N), phosphorus (P) and potassium (K)- as well as a host of other trace elements, which are present in the soil in smaller quantities.

Nitrogen is essential for the formation of plant tissue and leafy growth. Demand for it is particularly high when the plant is young and growth is rapid. Signs of nitrogen deficiency are poor growth and pale green, sickly-looking leaves. Phosphorus is needed for root development, and it helps the plant to retain water. Signs of phosphorus deficiency are red or purplish discolorations underneath the leaves. Potassium is used most notably in the development of flowers and fruit. Signs of deficiency include brown curling leaf edges and lack of flowers and fruit.

All three nutrients are provided by soil organisms in the process of decomposing organic matter- so you are off to a good start if you have already prepared the soil with lots of manure or garden compost. If your soil is good, having been fed and nurtured for a number of years, then fertilizers in any form really aren’t necessary- in fact Garden Organic, Britain’s leading organic body, goes as far to say that fertilizers should never be used in good organic practice. But if you are just starting out on your allotment, some of your crops may need an extra boost in spring to maximize your harvests. Brassicas, generally, are greedy feeders and will benefit from a nitrogen-rich fertilizer, while a phosphorus-rich fertilizer, like bonemeal, can benefit potatoes and other root crops. Organic, non-chemical fertilizers made from plant or animal sources are widely available to buy, but you can also make your own liquid fertilizers from manure, compost or plants such as comfrey or nettles.

Organic Versus Chemicals:

Chemical fertilizers are widely available but are used less and less nowadays. They provide large injections of nutrients and work very fast, promoting unnaturally swift growth. This can sometimes take the flavour away from vegetables, making them watery, and also opening them up to attacks from pests and diseases. Perhaps more than anyyhing else though, the chemicals in these fertilizers damage the delicate balance of the soil, destroying the micro-organisms that keep the soil healthy, so you are actually doing more long-term damage than good applying them.

Organic Fertilizers:

Bonemeal is a phosphate-rich fertilizer for promoting strong root growth.

Chicken manure pellets are high in nitrogen and good for leafy vegetables.

Fish, blood and bone is a good balanced all-round fertilizer.

Hoof and horn is nitrogen-rich and good for leafy vegetables.

Rock and potash is high in potassium and is good for potatoes and tomatoes

Seaweed meal is a general tonic with many trace elements

Wood ash from your own bonfires is high in potassium (do not use coal ash it contains toxins)