Plant Nutrition basics for start up crop farmers in South Africa.

Like all living things, plants need food to maintain physiological processes, grow and reproduce. Even though food is complicated or broad, their anatomy is made up of elements which serve different purposes to be able to function and sustain life. In the case of plants, they require or consume food by up taking them with their roots as minerals concentrations, process them as elements for metabolism, development, growth and reproduction purposes-this is what we simply call plant nutrition. Plants require some elements in high quantities and some elements in small quantities in order to satisfy their nutrition.

The elements plants require in huge quantities (abundance) are called Marco nutrients and element needed in small quantities are called micronutrients. Elements that are needed in large quantities are Nitrogen(N) Phosphorus(P), Potassium(K), Calcium(Ca), Sulphur(S), Magnesium(Mg), Carbon ?, oxygen (O) and Hydrogen (H). Examples of micro nutrients also known as trace elements are Boron(B), Chlorine(Cl), Zinc(Zn), Iron(Fe), Molybdenum(Mo), Manganese(Mn) Nickel(Ni) and Copper (Cu) which are needed by plants in small quantities to satisfy their needs as well as ensure successful yield cultivation. In most cases plants obtain these sources of nutrients by using their roots as their mouth. Therefore elements involved in plant nutrition come mostly from the soil, except some nutrients that come from the atmosphere These elements are gases such as Oxygen(O), Carbon (C) Hydrogen (H) as well as Nitrogen(N) that needs to be fixed in a way that plants are able to consume it. The amount of nutrients in a soil depends on the environment, type of rocks present, weathering, erosion and human or life activities that has taken place in the area.

Activities such as domestication and farming systems also impact the amount of nutrient content found in a certain area soil. In the case where nutrients are limited by unavailability organic or synthetic fertilizers are used to supplement depleted nutrients to create balance for successful plant utilization, quality and quantity yield production. Remember plants require nutrients differently, depending on their classifications, intended purpose of production and growth stage, but each plant group requires a unique balanced diet. If the plant does not get the necessary nutrients it needs to grow and reproduce, it will show symptoms either with the appearance, limited growth, lack of reproduction and even become susceptible to disease. Now if you are a farmer that would result to great losses of production as well as return of investment. It is better to understand what plant nutrition is, so that one can be able to manage their crops with success. This case study is mainly about understanding the basis of plant nutrition so that we can all become successful plant managers and farmers.

Plant nutrient deficiency

When mineral elements lack in the soil and do not satisfy plant requirements for metabolism, growth and reproduction that is called plant nutrient deficiency. Plant nutrient deficiency is a huge problem in agriculture with consequences such as distorted growth, improper development, diseases and plant toxicity likely to occur. Remember plants use nutrients for plant metabolism, growth, and reproduction, therefore if there is a deficiency, successful yield cultivation will be limited. When plants lack nutrients, they grow slow, do not develop properly resulting to a distorted or stunted growth. Crops have poor bud or sprouts setting as the plant does not have sufficient energy to produce plants parts (leaves, branches, reproductive parts) necessary for plant development. The height of the plant becomes stunted, distorted as growth is limited, due to the lacks of necessary nutrients to required grow.

Leaves of plants that suffer from nutrition deficiency develop slow, improperly and also suffer from discoloration when it doesn’t obtain nutrient elements such as Nitrogen and phosphorus. Yellowing of the leaves is one of the symptoms that show plants lack Nitrogen and purple discoloration of leaves, especially those that are normally green, accounts for phosphorus deficiency. At some point the plant fails to develop reproductive parts due to failure to reproduce to leaves and buds. This results to plants not forming flowers nor setting fruits, leading to lower yield quantity for a crop farmer, especially with photosynthesis impacted by yellowing. In some instances, if the flower or fruits is set, the plant produces products that is of low quality in terms of size, color, texture, content (sugar, acid, minerals or salt)and skin.

Another danger to plant nutrient deficiency, is that when plants lack nutrients elements, they develop diseases. This is because when plants lack nutrient elements their immunity is weak, therefore they become victims to diseases such as necrosis, chlorosis wilting and the plant is susceptible to other pests, diseases, frost as well as hail damage. Lastly the challenge with imbalanced plant nutrients in the soil, toxicity may also occur resulting to plant death.

In acidic conditions Aluminum (Al) results to toxicity in the soil, while in alkaline conditions, Boron (B) and Sodium (Na) lead to toxicity, which kills the plant gradually. Remember these elements are micro nutrients meaning that they are required in small amounts, therefore if they are in abundance this result to toxicity or it could just be a chemical reaction. The main thing about plant nutrition deficiency is that it reduces quality and quantity production yields for a farmer, meaning that impacts income or return of investment. In order to avoid this problem, it is better to know what is in your soil and what your plant requires for proper management as well as revenue generation.

How do you know the minerals in your soil

The only possible way to know the nutrient status in the soil and their quantities is to do a soil test, where by samples are taken from the soil of your farm and then tested in a lab. The results of the soil test and analysis will tell you the nutrients that are available in the soil as well as quantity amounts. Furthermore, a soil test and analysis will recommend supplementation of nutrients that are unavailable in the soil and amount required to satisfy plant needs. A leave test is another test done by taking samples of young leaves as they give the best accurate results of nutrient status in the plant. The test together with the analysis assists in knowing the nutritional status of the plant in order to know what to supplement it with for good management. The supplementation of nutrients source can either be organic fertilizer such as animal manure and plant residue or inorganic synthetic fertilizers such as NPK, foliar sprays to mention a few. If you are a farmer one thing you are expected to know is the nutritional requirements of the desired crop to be cultivated. One must know what it nutrients are required, quantities needed to satisfy the plant and at what growth stage for proper management and successful cultivation.

Knowledge of a plant nutrition and the amount of nutrients you have in the soil needs to be done before planting, so that if there are fertilizer inputs needed, a farmer can be able to prepare or apply without unexpected costs during production. This is to balance nutrients in the soil therefore satisfy plant growth, especially because nutrition contributes so much to quality quantity yields. Doing a soil and leave test makes precision management, meaning that you know exactly how much of fertilizer inputs are needed in the soil to sustain production. Most farmers just randomly apply fertilizer without knowing the available nutrients, their amounts in the soil or not even knowing what the crop needs. The problem with that is that farmers incur unnecessary fertilizer costs as you might buy what it is already in the soil.

The plant might not use the fertilizer resulting to loss or might even cause plant death as too much of some elements lead to toxicity in the soil. In the culture of agriculture you cant just buy and apply fertilizer blindly without knowing the status of your soil, plant and its requirements. This is why sometimes a farmer can apply fertilizer but still not obtain desired results even though practices have been done accordingly. Some nutrients create an acidic, alkaline or even toxic environment when they are excessive in the soil impacting plant production. So a soil test and leave test help with knowing nutrients, their availability so that you can supplement what is only needed, avoiding unnecessary fertilizer costs and even diseases from ph. or toxicity. For more information on plant nutrition, soil tests and analysis please contact us at Bambooagri