By Gabriella Nashiva
Soil is a natural resource and it’s where the roots of plants are anchored helping them absorb water, nutrients and mineral salts, in addition to the support. Soil fertility is the intrinsic ability of the soil to supply a plant with nutrients in the correct ratio and in the form available to the plant. So what really indicates that your soil is fertile. Simple, there are four indicators of soil fertility: good drainage and aeration to avoid water logging as well as carbon dioxide accumulation, the pH should be right for the desired crop last but not least the availability of nutrients to crops in the right amounts and ratio to one another.
Loss of soil fertility seems like a dead end and appears to be permanent but it isn’t. For starters, loss of soil fertility could happen as a result of soil erosion where the yummy nutrients are washed away by running water, leeching where some of the nutrients in form of mineral salts readily dissolve in water hence being lost. Some minerals are lost through volatilization which means that they are lost as vapor when applied in hot weather this happens for nitrogenous fertilizers. Other minerals become fixed to the soil thus unavailable to the crop. Also, nutrients get used up by microorganisms in the soil or the crops for their nourishment and become unavailable over time raising the need for replenishing.
The importance of improving and maintaining soil fertility should be emphasized if a healthy harvest is your big picture. Always ensure you have put in place measures to control soil erosion on your farm. Crop rotation preferably each season results in a balanced use of nutrients. Mulching is a brilliant way to ensure soil nutrients and microorganisms are protected from erosion and heat too.
Organic matter and organic manure trends (Use of Snails etc)
Compost manure is a mixture of different decayed organic waste materials such as leaves, weeds, lawn cuttings and pruning waste. Small amounts of nitrogenous fertilizer may be added onto the heap at regular intervals so as to speed up decomposition. Compost manure provides humus the best source of nutrients for plants, the more decomposed the manure is the better the nutrient value.
Green manure also known as cover crops has been used by farmers’ especially small scale ones for decades. It is growing of plant crops in between the main crop to provide soil cover and improve quality of soil boosting soil fertility and farm productivity. Legumes are the commonly used crop. Green manure minimizes soil erosion by reducing the impact of rain droplets as it lands on soil hence the name cover crops. To top it up, they are natural weed controllers! They suffocate and kill weeds by taking up nutrients that are not in use by plants. Legume research network in Kenya conducted studies that concluded that green manure used together with farmyard manure saves you the cost of buying chemical fertilizers.
Farm yard manure is best obtained from animals that do not extract a lot of nutrients from the feeds they consume such are mainly fattening animals or young ones. The quality of the manure however will be determined by various factors such as the quality of feeds the animal fed on, the animal, level of decomposition among others.
Fertilizers are applied to improve quality and quantity of crops with each crops having a specific fertilizer need. Fertilizer application in the right amounts based on fertilizer analysis is important. This analysis includes analyzing; Nutrient deficiencies, Soil types, Climatic conditions as well as crop type.
An improper fertilizer application may result in a complete loss of the applied plant food nutrient. It is very vital to understand why you are applying the fertilizer and how you are applying it including if there is need for safety gear, duration for application and correctly locating where you are supposed to apply.
Water soluble fertilizers can be administered to crops together with their water in irrigation; this practice is known as Fertigation. Fertigation can be used to administer fertilizers, pesticides and soil amendments practice. The pros being, it reduces the risk of leeching and erosion and easy farm management as it reduces the time that would be otherwise spent on crop inspection commonly known as scouting. The cons are that with minimal inspection, early detection of problems in the field goes unnoticed. In addition, you cannot apply compost, humus or any other top manure.