Introduction 

• A piece of land which is prepared is known as seedbed. 

• A seedbed is a piece of land that is prepared ready to receive planting materials. 

Seedbed Preparation 

Reasons for Seedbed Preparation; 

• To enable water to infiltrate. 

• To kill weeds 

• To improve soil aeration. 

• To destroy pests and diseases. 

• To incorporate organic matter in the soil. 

• For easy planting. 

• To facilitate root penetration. 

Operations in Land Preparation 

Land Clearing 

• Clearing of land is necessary when: 

• Opening up a virgin land. 

•    A stalk growing crop was previously planted. 

• There is long interval between primary and secondary cultivation. 

• Land was left fallow for a long time. 

Procedure 

• Tree felling and removal of stumps and roots. 

• Burning 

• Slashing 

• Use of chemicals. 

     Note: Burning should be avoided where possible since it;

• Leads to loss of organic matter,

• Kills soil organisms 

• Destroys soil structure and plant nutrients. 

Primary Cultivation 

• This is the initial breaking of land. 

• It is done early before the onset of the rains to: 

- Give time for soil organisms to act on organic matter. 

- Allow gaseous exchange to take place, thus carbon dioxide diffuses out of the soil while oxygen enters into the soil. 

- Allow other operations to take place in time. 

Reasons for primary cultivation: 

• Remove weeds. 

• Burry organic matter. 

• Open up soil for infiltration of water and air. 

• Expose pests and disease causing organisms. 

• Soften the soil for easy planting. 

Operations in primary cultivation

• Hand digging ; 

     Use of hand tools ; 

- Jembes, 

- Mattocks, 

- Fork-jembes. 

• Mechanical cultivation ;

   Use of mouldboard ploughs; 

- Disc ploughs, 

- Chisel ploughs,

- Subsoilers 

- Rippers. 

• Use of Ox-Ploughs ;

    Which can be drawn by;

- Oxen,

- Donkeys, 

- Camels 

Depth of Cultivation 

  Depends on: 

• The type of crop to be planted/size of seed. 

• The implements available. 

• The type of soil. 

Choice of Implement 

   Determined by: 

• The condition of land. 

• The type of tilth required/type of crop. 

• Depth of cultivation.

Secondary Tillage 

• These are refinement practices on the seedbed that follow primary cultivation. 

• It is also known as harrowing. 

Reasons for secondary Tillage: 

• To remove the germinating weeds. 

• To break soil clods to produce required tilth. 

• To level the seedbed for uniform planting. 

• To incorporate organic matter/manure into the soil. 

Factors determining number of secondary cultivation: 

• Soil moisture content. 

• Size of the planting materials. 

• Condition of the soil after primary cultivation. 

• Slope of the land. 

Tertiary Operations: 

• Ridging ;

- The process of digging soil on a continuous line and heaping on one side to produce a furrow and a bund (ridge). 

- It is important for root crops, to allow root expansion and for soil and water conservation. 

• Rolling: 

- It is the compaction of the soil to produce a firm surface which increases seed-soil contact and prevents wind erosion. 

• Levelling;

- Production of an even, uniform surface which promotes uniform planting. 

Subsoiling: 

• This is deep cultivation into the subsoil layer to break up any hardpan which might have developed. 

It is done for the following reasons:- 

• To facilitate drainage. 

• Bring up leached nutrients to the surface. 

• Increase aeration of the soil. 

• To improve root penetration. 

• The implements used include chisel plough and subsoilers. 

Minimum Tillage: 

• This is the application of a combination of farming practices with the aim of reducing the disturbance of the soil. 

Examples of which include: 

• Use of herbicides. 

• Mulching and cover-cropping. 

• Timely operations to prevent weed infestation. 

• Strip cultivation. 

• Uprooting and slashing of weeds. 

Reasons for Minimum Tillage 

• To reduce cost of cultivation. 

• To control soil erosion. 

• To preserve soil moisture. 

• To prevent root exposure and damage. 

• To reconstruct destroyed soil structure.