× Home News KTN Farmers TV Smart Harvest Farmpedia Farmers Market Mkulima Expo 2021 Agri-directory Digital News Videos Health & Science Lifestyle Opinion Education Columnists Moi Cabinets Arts & Culture Fact Check Podcasts E-Paper Lifestyle & Entertainment Nairobian Entertainment Eve Woman Travelog TV Stations KTN Home KTN News BTV KTN Farmers TV Radio Stations Radio Maisha Spice FM Vybez Radio Enterprise VAS E-Learning Digger Classified Jobs Games Crosswords Sudoku The Standard Group Corporate Contact Us Rate Card Vacancies DCX O.M Portal Corporate Email RMS

Home / Smart Harvest

Struggling with poor yields? Check your soil

Good harvest starts with the soil. However, farmers often ignore significance of good soil preparation on the overall performance of the crop. 

No crop will grow well without healthy, fertile soil. It’s like expecting a baby to grow into a healthy adult without food and water. Good soil not only stabilises plants and influences how well roots are anchored, but also provides the essential nutrients, water, and air that plants need. If you start with poor soil, your crops will struggle to achieve full potential. To achieve this, you need to understand the chemistry and composition of your soil and create desirable environment for your crops to thrive. Good soil take time to achieve, it is a process, but once you master the basics, it becomes easier.

Soil History

The history of your farm and how the soil has been used is important in making decisions on how to improve the soil. Understand the history of your farm, identify the type of plants that have been grown, type of fertiliser or manure that has been applied, and which crops performed well or those that performed poorly. These indicators will help reveal the potential limitations of your soil.

Understand soil type

Soils are composed of mineral particles which are primarily clay, sand and silt. Often they will contain higher amounts of one type of particle relative to the others. That doesn’t make them bad growing mediums, but it will affect their density, drainage rate, and capacity to hold nutrients. Clay soils have tiny, dense particles that hold large reserves of moisture and nutrients. However, clay soil also drains slowly and can become hard and compacted when dry. Sandy soils are the opposite, with large particles that water moves through easily along with important nutrients. Silts have fine particle sizes that pack together tightly, inhibiting drainage and air circulation. Loam is the ideal soil for most plants; it contains a balance of all three mineral particles and is rich in humus. Adding organic matter is the best way to make your soil more loam-like and improve its structure.

Members of Esteem Eagles Welfare Youth group in their greenhouse fitted with an hydroponics system. The technology enables them to grow tomatoes, capsicum and other high value plant without using soils which minimise chances of diseases. [Phares Mutembei, Standard]

Test the pH of your soil
The pH of your soil is one of the most important factors in determining its fertility. If your soil is too alkaline (with a pH above 7.5) or to acidic (with a pH below 5.5), that can make a big difference in which nutrients are available to your plants. Although most plants will tolerate a wide range of pH levels, they prefer slightly acidic soils (with a pH of 6 to 7) because important nutrients such as nitrogen, phosphorus, potassium, calcium and magnesium dissolve readily in that environment. In soils that are too acidic or alkaline, your plants may get too much of some nutrients and not enough of others.

To raise the soil pH, add limestone. Limestone should be applied at least two to three months ahead of planting to give it time to work. Wood ash can also raise the pH of soil, but care must be taken in its use. Applying too much wood ash may result in high pH readings and take nutrients from your soil. If using wood ash every year, keep a close eye on your soil’s pH and stop using it when the proper reading is achieved. Alkaline soil on the other hand, needs to be made more acidic. This can be done with the addition of sulfur, sawdust, conifer needles, sawdust or oak leaves.

Cover Crops

Cover crops are a temporary planting, usually sown in the fall, that help protect the soil from wind and erosion and add valuable organic material. They also establish a dense root structure that can have a positive effect on soil texture. Cover crops also suppress weeds, deter insects and disease and help fix nitrogen. When the crops are turned into the soil, they become green manure. Rye and alfalfa are common cover crops. Cover crops are planted at the end of the growing season or during part of the growing season itself. 

Share this story

Stay Ahead!

Access premium content only available
to our subscribers.

Support independent journalism