Soil analysis results inform the farmer of deficiencies or excesses, if any, of minerals. They also advise on the correct type and amount of fertilizers to apply. They also enlighten on the method and time of application of fertilizer.

The genesis of low yields today in our farms year by year originates to lack of our beloved farmers not having full information on how their soils nutrient value is. To achieve high and quality yields a farmer has to determine the level of nutrients availability, to provide the basis for calculating the required fertilizing of each crop and to evaluate the supply of each nutrient element and determine how to manage the nutrient. High quality soil analysis is basis of planning of fertilizing, and thus the quality of the entire production cycle, which results in a high quality and yield and better farm management.

NOTE; Soil acidity (pH), which rarely affects the growth of most crops directly in the range 5.5-7.5 but can influence the availability of other nutrients.

Soil analysis determines the content of basic plant nutrients; nitrogen (N), phosphorus (P2O5), potassium (K 2 O), pH, humus content, total CaCO3, available lime, organic matter, total sulphur (S), trace elements, and other physical characteristics (capacity, permeability, density, pH - value).

Here are some of the plant nutrient deficiencies;

Plants can also suffer deficiencies where the growing conditions are poor and the plants are unable to take up nutrients present in the soil. Very acid or alkaline conditions, dryness and water logging can all make it difficult for plants to take up soil nutrients.

http://oxfarm.co.ke/tree-fruits/paw-paw/pawpaw-farming-in-kenya/

Nutrient deficiencies cause symptoms such as leaf yellowing or browning, sometimes in distinctive patterns. This may be accompanied by stunted growth and poor flowering or fruiting.

Macro nutrient

 Nitrogen

comparance of a nitrogen deficient plant and a healthy plant

How to identify

Check the field for abnormalities. N deficient crops are stunted and discolored. Specifically:

  • Older leaves or whole plants are yellowish green
  • Old leaves and sometimes all leaves become light green and chlorotic at the tip
  • Entire field may appear yellowish.

 

Phosphorous

How to identify

[caption id="attachment_4138" align="alignleft" width="250"] phosphorous deficient plant[/caption]

  • Slow and stunted growth.
  • Leaves may curl
  • Leaves become purplish (or reddish-purple), most often first on their undersides and later on the tops.

 

 

 

 

Potassium

How to identify

  • On the oldest leaves, yellowing occurs in marginal and interveinal zones.
  • Brown scorching and curling of leaf tips as well as yellowing between leaf veins.
  • Plant growth, root development, and seed and fruit development are usually reduced.
  • Yellow stripes may appear along leaf interveins and lower leaves may bend downward. [caption id="attachment_4139" align="alignleft" width="253"] potassium deficient plants[/caption]

 

 

 

 

 

 

Magnesium

How to identify

  • Yellowing of the leaf structure found between veins.
  • Older leaves turn yellow at the edge giving a green overhead shape at the Center of the leaf.

Calcium

How to identify

  • New leaves appear distorted or irregularly shaped.
  • Development of necrotic tissue on young leaves.
  • In severe cases root tips may die back.[caption id="attachment_4140" align="alignleft" width="300"] calcium deficient plant[/caption]

 

 

 

 

 

 

Sulfur

How to identify

  • Uniform pale green chlorosis throughout the plant.
  • Youngest leaves may appear pale earlier or more severely than mature leaves.
  • Yellowing of the leaves, but nitrogen deficiencies begin with the older leaves first.

Micro nutrients

Boron

How to identify

  • Thickening of young leaves.
  • The leaves and stem near the shoot tip are brittle and break easily when bent.
  • Young leaves are usually paler than the older leaves.

Manganese

How to identify

  • Leaves become yellow and there is also interveinal chlorosis.
  • Pale grayish green interveinal chlorosis spreads from the tip to the leaf base.
  • Necrotic brown spots develop later and leaf becomes dark brown.
  • Newly emerging leaves are short, narrow, and light green

Copper 

How to identify

  • Dieback of stems and twigs.
  • Yellowing of leaves.
  • Stunted growth and pale green leaves that wither easily.

Iron

How to identify

  • Leaf yellowing first appears on the younger upper leaves in interveinal tissues.
  • Leaves to turn completely yellow or almost white, and then brown as leaves die.

Zinc

How to identify

  • Short internodes and a decrease in leaf size.
  • Delayed maturity[caption id="attachment_4141" align="alignleft" width="300"] zinc deficient plants[/caption]

 

 

 

 

 

 

 

Benefits of testing farm soil.                     

  • The world population is growing up and thus fertile soils are required to produce more food.
  • Farmers can easily avoid soil degradation.
  • Leads to minimization of fertilizer expenditure.
  • Informs the farmer on the current health status of the soil.

Appropriate time to take the soil sample

Soil samples can be taken any time throughout the year. However, it’s also appropriate to take soil samples after the harvest. This will give you ample time to prepare the land as per the recommendations of the soil sample results before the next planting season. The soil should not be too dry or wet when taking the soil sample in a farm. In orchards where there are permanent crops, soil test should be done after every four years.

OxfarmAg Ltd message to Kenyan farmers;

Smallholder farmers, particularly those in Kenya, often lack access to soil testing laboratories to determine their soil’s fertility and the nutrients required to increase crop productivity. This causes farmers to apply fertilizer that may not meet their soil’s needs. Soil analysis will inform you of your soils' deficiencies. Soil testing can also help to predict return on investment for Kenyan farmers.

Here at oxfarm we have dedicated staff with a primary goal of providing accurate soil analysis in a timely manner.

Frequent soil testing helps farmers decide whether their current management is robbing future productivity and profits.

Soil testing serves as the best guide available for determining nutrient needs for growing crops. Soil testing also provides a balanced fertility program which is a vital component of sustainable farming programs that are profitable, efficient and environmentally responsible.

We offer soil testing services at highly competitive prices and this will assist a farmer to undertake the correct management practices in his farm.

We offer individual package of soil testing at ksh 2800 per sample exclusive of transport which is charged at ksh 20 per km from Nairobi to the farm and back when coming to collect the soil sample.

Contact us on  0706222888.