Maize feeds hundreds of millions across Africa and is a reliable cash crop for smallholders and commercial farms alike. Yet average yields often remain below potential. The biggest gains come from doing the basics—consistently and correctly. This guide distills field-tested practices you can apply this season to lift yields and profits.
1) Plant Improved, Locally-Adapted Varieties
Choose hybrids or open-pollinated (OPV) lines bred for your zone (rainfall, altitude, heat/drought, disease pressure).
Prioritize traits: drought/heat tolerance, early maturity, disease resistance (e.g., maize streak virus), and lodging resistance.
Buy certified seed each season for hybrids; OPVs can be replanted for a few cycles but yields are usually lower than hybrids.
Tip: Early-maturing hybrids help you “escape” late-season droughts and fit double-cropping calendars.
2) Get the Soil Right: Test, Amend, and Prepare
Soil test every 2–3 seasons for pH and nutrients.
Target soil pH 5.8–6.5; if lower, lime (typ. 1–2 t/ha) 2–3 months before planting.
Incorporate well-decomposed manure/compost (2–5 t/ha) to boost organic matter, water holding, and microbial life.
Land prep: Aim for a fine, weed-free seedbed with good tilth and residue managed (retain some residue for moisture, but avoid heavy mulch that harbors pests).
3) Plant at the Optimal Time (Don’t Chase the Rains)
Plant with the first effective rains (25–40 mm over 3–5 days) to ensure establishment, especially in unimodal rainfall areas.
In bimodal regions, align with the main rainy window; early planting reduces pest pressure and takes advantage of longer growing periods.
Nigeria example (guideline, adjust locally):
South: March–April (main), Aug–early Sept (second).
North: May–June (main).
4) Hit the Right Plant Population and Spacing
Target 50,000–60,000 plants/ha under rain-fed conditions; 65,000–75,000 plants/ha under irrigation/high fertility.
Common spacing options (1 plant per stand):
75 cm × 25 cm → ~53,000 plants/ha
70 cm × 25 cm → ~57,000 plants/ha
90 cm × 30 cm → ~37,000 plants/ha (too low for many systems)
How to plant:
Depth 3–5 cm (shallower in heavy soils; slightly deeper in sandy soils).
Seed rate usually 15–25 kg/ha, depending on seed size and expected field losses.
If you drop 2 seeds/stand, thin to 1 at 10–14 days after emergence to keep uniform stands.
5) Feed the Crop: Smart Fertility Management
Where no soil test exists, a pragmatic baseline per hectare is:
Nitrogen (N): 120 kg
Phosphate (P₂O₅): 60 kg
Potash (K₂O): 40 kg
Example program (adjust to local fertilizers):
Basal at planting: 300–400 kg/ha NPK 15-15-15 (supplies 45–60 kg each of N, P₂O₅, K₂O).
Topdress: Enough urea (46% N) to bring total N to ~120 kg/ha (≈130–160 kg urea/ha), split into 2 applications:
V4–V6 (3–4 weeks after emergence): half the urea
V8–V10 (6–7 weeks after emergence): remaining half
Micronutrients: In deficient areas, zinc and boron can pay off. Foliar feeds help in-season but don’t replace solid fertility.
Organic integration: Combine mineral fertilizer with 2–5 t/ha of compost/manure for better soil health and resilience.
6) Manage Water: Critical Stages Matter
Maize needs ~500–800 mm of water per season. Yield is most sensitive 3 weeks before to 2 weeks after tasseling/silking.
Irrigated/partially irrigated farms: Maintain soil moisture at ~50–70% of field capacity; avoid stress at tasseling, silking, and early grain fill.
Rain-fed farms: Use mulch, ridges, tied ridges, zai pits, and residue retention to conserve water and reduce runoff.
Fix drainage issues early—waterlogging kills roots and slashes yields.
7) Keep the Field Clean: Weed Control on Time
Weeds rob maize of water and nutrients, especially in the first 6–8 weeks.
Critical windows:
1st weeding: 2–3 weeks after emergence (WAE)
2nd weeding: 5–6 WAE
Pre-emergence herbicide (where permitted and label-approved) plus timely manual/mechanical weeding gives strong control.
In conservation agriculture, use cover crops (e.g., cowpea) or residue mulch to suppress weeds.
Safety note: Always follow herbicide labels, PPE, and local regulations.
8) Prevent and Control Pests & Diseases (IPM)
Scouting: Walk fields weekly (early season: every 5–7 days). Treat when thresholds are reached rather than by calendar.
Key threats & actions:
Fall Armyworm (FAW): Look for whorl feeding, frass. Early action matters.
Cultural/low-cost: Early planting, handpicking egg masses/larvae, ash or soap solutions in the whorl (traditional), balanced nutrition.
Biological: Bacillus thuringiensis (Bt) products, natural enemies.
Chemical (where necessary): Rotate modes of action (e.g., emamectin benzoate, spinosad, lufenuron). Spray in late afternoon; target the whorl. Respect PHI/REI.
Stem borers: Early planting, destroy crop residues, use resistant varieties; targeted sprays if needed.
Maize streak virus: Control leafhopper vectors by early planting, weed control, and using resistant varieties.
Storage pests (weevils, larger grain borer): Dry grain to ~13% moisture and store hermetically.
9) Reduce Losses at Harvest, Drying, and Storage
Harvest when husks are dry and kernels are hard (grain moisture ~20–25%).
Dry quickly to ~13% for safe storage (cob cribs, tarps, or solar dryers; avoid direct ground contact).
Shell carefully to minimize breakage.
Store in hermetic bags (e.g., triple-layer/PICS) or sealed bins to stop insects without routine insecticide dusts.
Keep stores dry, raised, and rodent-proof; inspect monthly.
10) Rotate, Integrate, and Keep Records
Rotate with legumes (soybean, cowpea, groundnut) to break pest cycles and boost soil nitrogen.
Avoid continuous maize–maize; where land is tight, use strip cropping or intercrop maize with a legume that doesn’t heavily compete (wider rows, staggered planting).
Records: Track dates, inputs, rainfall/irrigation, pest events, yields. Data shows what truly worked and where to invest next.
Practical Field Recipes
A. Quick Spacing & Population Guide (1 plant/stand)
75 × 25 cm → ~53,000 plants/ha
70 × 25 cm → ~57,000 plants/ha
60 × 25 cm → ~66,000 plants/ha (good under irrigation/high fertility)
B. Sample Fertilizer Schedule (no soil test; rain-fed; medium soils)
Planting: 350 kg/ha NPK 15-15-15 (band 5 cm beside/below seed)
Topdress 1 (3–4 WAE): 70–80 kg/ha urea
Topdress 2 (6–7 WAE): 70–80 kg/ha urea
Organic: 2–5 t/ha compost or manure before planting
(Always adapt to local recommendations and prices.)
Common Mistakes (and Fixes)
Late planting → Plant with first effective rains/irrigation.
Low plant population → Re-calibrate spacing; replant gaps early.
One-shot nitrogen → Split applications; side-dress before rains/irrigation.
Weeding too late → Keep field weed-free during weeks 2–8.
Ignoring pH → Lime acidic soils; nutrient use efficiency jumps.
Poor drying/storage → Dry to ~13% and use hermetic storage.
Budgeting for Profit
Focus spend on proven ROI items: certified seed, timely N, soil amendments where deficient.
Buy inputs early (pre-season) to avoid price spikes.
Aggregate sales (co-ops, off-taker contracts) for better prices; consider shelling and grading to earn a premium.
Measure cost/ha and yield/ha every season to track margins.
Frequently Asked Questions
Q1: What’s the best spacing for smallholders without irrigation?
A: 75 × 25 cm (≈53,000 plants/ha) is a reliable target on most medium-fertility, rain-fed fields.
Q2: How much fertilizer if I can’t afford the full rate?
A: Prioritize N at early growth and near tasseling. Even 200–250 kg/ha NPK 15-15-15 + 80–100 kg/ha urea (split) can lift yields significantly compared to no fertilizer—especially when combined with manure.
Q3: How do I know when to control FAW?
A: If ≥20% of plants show fresh whorl damage in early growth, act. Start with cultural/biological control; escalate to approved chemicals if needed, rotating modes of action.
Q4: Can I intercrop maize and legumes?
A: Yes—if you manage spacing and timing so the legume doesn’t out-compete maize during weeks 2–8. Many farmers prefer rotation for maximum maize yield.
Final Checklist Before Planting
[ ] Certified, adapted seed acquired
[ ] Soil tested / plan for lime or manure if needed
[ ] Planting date aligned with first effective rains
[ ] Spacing tools (string/markers) ready
[ ] Basal fertilizer and topdress urea secured
[ ] Pre-emergence weed plan & weeding labor scheduled
[ ] FAW scouting plan and safe-use PPE available
[ ] Drying sheets/tarps and hermetic bags ready
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