14/05/2026
Week 4 in maize farming is a very critical physiological stage.
Get Scientific-Oriented agronomic support by The Soil Doctor
At this point, the crop transitions from early establishment into aggressive vegetative growth. Root expansion increases rapidly, nutrient demand rises sharply, and the plant begins preparing its photosynthetic engine that will determine future cob formation and yield potential.
Scientifically, this is the stage where farmers should focus heavily on:
• Root development
• Nitrogen availability
• Soil microbial activity
• Moisture management
• W**d suppression
• Early pest and disease monitoring
Nitrogen becomes highly important because the plant is actively producing chlorophyll and leaf biomass. Deficiency at this stage often appears as yellowing starting from older leaves due to nitrogen remobilization.
The root zone also becomes extremely active. Beneficial microorganisms such as Bacillus spp., Azotobacter, and mycorrhizal fungi help:
• Improve nutrient uptake
• Enhance phosphorus availability
• Stimulate root growth
• Improve drought resilience
• Suppress soilborne pathogens
This is why healthy soils often produce stronger and darker green maize compared to chemically stressed soils with poor biological activity.
At week 4, proper soil moisture is equally essential. Water stress during this stage can reduce cell expansion, limit root growth, and eventually affect yield potential later during tasseling and grain filling.
Farmers should also monitor for:
• Fall armyworm
• Nutrient deficiencies
• Stunted growth
• Leaf discoloration
• Waterlogging stress
• W**d competition
W**ds at this stage compete aggressively for nitrogen, moisture, and sunlight. Early control prevents major yield losses.
A healthy 4-week maize crop should exhibit:
• Vigorous upright growth
• Uniform stand establishment
• Deep green leaves
• Strong root anchorage
• Active new leaf emergence
Remember:
Yield is not built during harvesting.
It is built during the vegetative stages.
Strong roots today become heavy cobs tomorrow.