Healthy soil that is used to grow our food needs assistance to stay that way, as plants grow they deplete the soil of its nutrients and moisture. Healthy soil also aids in the conservation of water, meaning less irrigation.
Healthy plants attract less destructive pests, so will need less chemical intervention and will lead to healthier people.
There are many ways of improving the health of the soil, and for many years gardeners and farmers have reached for chemical fertilisers to assist them in producing larger, and faster, crops. However, the move toward sustainable use of the earth is leading to more organically friendly ways of fertilising our vegetables and fruit.
What is Fertiliser?
According to the dictionary it is: a natural or chemical substance that is spread on the land or given to plants to make the plants grow well.
Well, it seems to me the natural way sounds much healthier.
Biochar is one of those things that could make a huge difference to the way we treat our soil. Biochar is charcoal made from plant material and agricultural waste and is one of the many things that can aid in improving soil condition. It is a fine-grained charcoal produced from the slow burning of organic matter in a low- or no-oxygen environment. It is used as an additive to soil to improve nutrient and water retention, and carbon storage (to mitigate greenhouse gasses). For an academic article on Biochar see here.
The technique of using charcoal to improve soil has its origins in the Amazon Basin 2500 years ago. The soil there today is rich and dark with a neutral pH.
pH is a scale of 0-14 that measures acidity/alkalinity of soil. A neutral pH is 7 and most of us would be happy if our reading was between 6 and 7. HOWEVER, this does not take into account the percentages of particular nutrients.
When our plants look sickly we usually go to the nearest outlet selling fertiliser, buy a bag, and add it to the garden. But, what are we buying? Most general fertilisers are a mix of N-P-K (Nitrogen, Phosphorus, & Potassium) and often the bags have varying proportions of each of those – e.g. N-P-K 6-5-5 means 6 parts nitrogen to 5 parts phosphorus and 5 parts potassium. All well and good, but some may be 20-5-5 etc. As we will see as we go along different plants need different amounts of these essential nutrients, so surely it is healthier for our soil and plants (and by association us) to add these nutrients separately or through natural methods. Besides the 3 essential nutrients (N-P-K) fertilisers will contain trace elements such as Zinc and Boron, again every plant has its own needs and will give you signs as to deficiencies or over abundances.
Over the next year we will be moving to a no till, no additives style of gardening, so stay tuned for updates.
Nitrogen
Nitrogen is one of the more elusive plant nutrients. Its availability depends on numerous other factors such as moisture, condition, and the active organisms in the soil. Nitrogen is essential for plant growth, and it is required for photosynthesis (greening) to occur.
Phosphorus
Needed for good root growth, plant maturity and photosynthesis (the use of sunlight and carbon to release oxygen).
Potassium
Aids the manufacture of sugars within plants, which has a direct bearing on a plant’s ability to resist diseases. It assists plants to cope with water and drought. Potassium also assists photosynthesis, particularly for plants in semi shade. Lastly, it encourages growth.
Calcium
It builds the cell walls of plant tissues and neutralizes acids produced by plants as toxic by-products of metabolism. It regulates the availability of other nutrients, builds plant proteins, and prevents magnesium toxicity.
Magnesium
Magnesium aids in a plant’s use of other nutrients, including nitrogen, phosphorus, and sulfur. What may appear as a phosphorus deficiency, for example, may be a magnesium deficiency that results in a plant’s inability to absorb phosphorus.
Sulfur
It helps plants produce proteins and enzymes, soil can struggle to retain sulphur especially if it is sandy.
Trace Elements
Nine nutritional elements exist as trace elements, and plants need them only in minute amounts. Oxygen, carbon, and hydrogen come from air. The other 6 are:
Zinc Zinc aids the creation of amino acids.
Boron Boron influences cell development and division, fruiting, flowering, stem growth, and a host of other plant activities.
Manganese Aids healthy growth.
Iron Plays major roles in the production of chlorophyll and in the nitrogen-fixation process. It also helps reduce nitrates to ammonia for the synthesis of plant proteins.
Copper Activates plant respiration and iron usage.
Molybdenum Aids in development of leaf growth