Page 12 - Simply Vegetables Summer 2022

Fertilisers:
The alternatives
Members will no doubt have observed that the price of fertilisers have increased greatly in the last six months and will increase further over the next six months to year. This is owing to the large increase in energy prices (which I am sure you are aware of!) which is why I am confident the fertiliser prices will continue to increase even if the energy prices reduce slightly. Since typing
this first sentence I have seen some research saying that fertiliser prices to commercial growers have increased by 240% from March 2021 to 2022 to both vegetable and top fruit growers and by 92% to soft fruit growers, the only cost to increase more is energy. We all need to find ways to reduce our fertiliser use but still maintain yields.
Many nitrogen fertilisers are manufactured using the Haber-Bosch process which uses large amounts of energy, the rock to make phosphate fertilisers is imported from the Middle East, South America, Morocco, and China so therefore have a high transport cost again owing to increased energy prices. Canada is the world’s biggest producer of potash followed by Russia and Belarus (so potash is likely to be in short supply for a while). Some of the potash used for fertilisers is mined in the U.K but this is still expensive and will increase owing to inflation.
So as vegetable growers what are our options?
look at using “homemade” substances
or locally produced material.
2. Avoid using fertilisers, this could be
done for a period of time as there will be some nutrients still available in the soil, but these will reduce over time and yields will reduce as this happens.
3. Use organic fertilisers like bonemeal, blood, fish and bone, hoof and horn, dried blood etc. these are also likely to increase in price and were not cheap in the first place, and some are imported so have a high carbon footprint.
4. Go a step further and use other organic materials some of which may not be
too expensive. Many of these materials are waste products from other food or industry production. This is what I will look at in the rest of this article and hope you can become more sustainable in your vegetable growing.
Firstly, I should point out the difference between organic fertilisers and organic matter or manure, the fertilisers usually have a higher amount of nutrient than organic matter and are more concentrated. The organic fertilisers will have come from something that has lived and includes bonemeal, dried blood, seaweed meal and chicken pellets. The amount of nutrients they contain is more than organic matter but usually less than artificial fertilisers; they are applied like fertilisers at the recommended grams a square metre. Artificial fertilisers are either mined or produced using industrial processes.
Organic matter, correctly called bulky organic matter is usually the waste product of animals or plants and often applied
Comfrey plants
1.
Pay the price, but that makes growing vegetables more expensive, and I do not want to wear my debit card out! We also need to become more sustainable and
Alfalfa green manure 2
at kilos per square metre (5 kilos being
a typical recommendation). It includes materials like farmyard manure (horse, cattle, sheep, goat), homemade compost, spent hops, spent mushroom compost, green waste compost (usually from the council green waste collection) etc. Its main use is to improve soil structure as well as adding some nutrients, the amount of nutrients is well below that of artificial fertilisers and often less than organic fertilisers so large amounts would be required to increase nutrient levels. Also, the amount of nutrients contained varies depending on the source of supply and even on what the animal has been fed on.
Using organic matter will be going back to old fashioned gardening in times before artificial fertilisers were widely developed prior to the Second World War, the days of the old fashion head gardeners! We are becoming more organic in our growing the Muck and Mystery brigade are being proven right and it should lead to healthier soils which are important from a climate change perspective as they hold more carbon.
Most manures and many other organic materials will contain a full range of nutrients including the macro-nutrients of nitrogen, phosphate, potash, magnesium, sulphur, and calcium as well as many of the micro-nutrients like iron, manganese, boron, copper, zinc, sodium and molybdenum. There are very few fertilisers that contain all these unless they are specially formulated. Unfortunately, unless you have the material analysed (which you
Adding leaf mold in greenhouse 2
Bed covered in compost
12 Simply Vegetables