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.