WATER HARVESTING FOR ASAL MAIZE PRODUCTION USING MODIFIED ZAI PITS

MAIZE PRODUCTION USING MODIFIED ZAI PITS

Women digging Modified Zai pit holes in Mivukoni, Kyuso, Kenya

Introduction

Maize is one of the most popular crops in agro ecological zone LM4 in Kyuso district. Kyuso district experiences an average annual rain fall ranging 300 to 600 millimeters in two seasons per year. Due to the erratic nature of the rains, there is a crop failure for 3 in every 5 consecutive seasons. This calls for water harvesting as an intervention to address the moisture shortage that causes the inherent crop failure. 

Modified Zai pits 
Zai pits as a water harvesting technology integrates a variety of factors to avail moisture to the growing crop to attain physi­ological maturity as follows:

• Cultivated (cropped) area: The soil condition of the cropped area must be well prepared to reduce any soil related limita­tions for optimum crop establishment and growth

• Catchment area: This must be sufficient to generate the extra moisture required in the form of runoff. A Catchment cropped area ratio of 3:1 has been found appropriate.

• Catchment characteristics: As much as possible the catch­ment should be modified to minimize infiltration. This may be achieved through increasing the catchment gradient towards the cropped area and compaction.

• Efficiency: In order to optimize the crop yield, both the normal rains and the runoff that collects at the cropped area must be used efficiently by the crop. All moisture losses must be minimized. The right crop variety with vigour must be planted early enough to gain from all the moisture experienced at the cropped area. It is advantageous to plant with Phosphorus containing fertilizers for early crop root establishment. Top dressing with Nitrogen and use of farm yard manure for provision of extra nutrients and moisture retention is necessary. Since weeds will compete for mois­ture and nutrients, weed control will be of necessity. Use of mulch will reduce evaporation losses. In addition since a health crop will use the soil resources efficiently, it will be necessary to protect the crop against pests and diseases.  Read More>>