Complete Farming Guide
Sorghum Farming Guide
Sorghum bicolor
62 million tonnes — the most drought-tolerant cereal on Earth
Sorghum is the fifth most important cereal crop globally and the dietary staple of over 500 million people in the semi-arid regions of Africa and Asia. Its extraordinary drought tolerance — surviving on as little as 300mm of rainfall — makes it the crop of choice where other cereals fail. Sorghum achieves this through a waxy leaf coating, deep root system, and the ability to go dormant during drought and resume growth when water returns. Beyond food, sorghum is increasingly important for animal feed, ethanol production, and gluten-free food products.
Quick Facts
Growing Season
Summer (Kharif)
Growth Period
90-130 days
Optimal Temp
25-35°C (77-95°F)
Water Needs
400-600mm
Top Producer
United States
Yield / Acre
2-4 tonnes/acre (US); 0.5-1.5 tonnes (Africa)
Sorghum Growth Stages — What to Do at Every Stage
Germination & Emergence
Days 0-10What to do
Plant when soil temperature at 2-inch depth is above 15°C (60°F). Plant at 1-1.5 inch depth, 3-6 inches apart in rows 30 inches apart. Apply pre-emergence herbicide — sorghum is sensitive to some herbicides (check label carefully). Seed treatment with insecticide for shoot fly protection.
Watch for
Shoot fly attack in the first 2 weeks — the #1 pest at this stage. Poor emergence from crusted soil. Bird damage on emerging seedlings.
Seedling & Vegetative Growth
Days 11-35What to do
Apply nitrogen (30-40 lb N/acre) as side-dress at the 5-6 leaf stage. Cultivate or apply post-emergence herbicide for weed control. Scout for shoot fly and stem borer. Thin to 4-6 inches between plants if stand is too thick.
Watch for
Shoot fly "deadhearts" — central leaf dies and can be pulled out easily. Stem borer entry holes at the base of plants. Yellow-green leaves indicate nitrogen deficiency. Sorghum is very sensitive to atrazine carryover from previous corn crops.
Boot Stage
Days 36-55What to do
Apply remaining nitrogen (20-30 lb N/acre). The head is developing inside the boot. Ensure adequate moisture — drought during boot stage reduces the number of seeds per head. Scout for aphids on leaves and emerging heads.
Watch for
Sorghum midge — the most critical pest timing. Midge adults lay eggs in flowers at anthesis (flowering). Charcoal rot from drought stress — dark discoloration at the stem base that leads to lodging.
Flowering (Anthesis)
Days 56-70What to do
Apply insecticide for sorghum midge if populations exceed threshold (1 midge per head). Flowers open from the top of the head downward over 5-7 days. Ensure water is available — this is the most yield-sensitive stage.
Watch for
Sorghum midge — tiny orange flies (2mm) on heads at dawn. Head bugs feeding on developing grain. Ergot (honeydew disease) — sticky, sugary ooze from unfertilized flowers, turning black with Sphacelia spores.
Grain Fill & Maturity
Days 71-130What to do
Monitor grain development. Grain passes through milk, soft dough, and hard dough stages. Harvest at 14-18% moisture for mechanical harvest. For hand harvest, heads can be cut and dried on-farm. Bird scaring may be needed throughout this stage.
Watch for
Bird damage — the #1 constraint in Africa. Grain mold complex (Fusarium, Aspergillus) in wet conditions at maturity, turning grain pink, gray, or black. Stalk lodging from charcoal rot — push plants to test stalk strength. Aflatoxin risk in grain stored above 14% moisture.
Common Sorghum Diseases — Identification Guide
Charcoal Rot
Macrophomina phaseolina
What you will see
Lower stalk discoloration (dark gray to black) visible when the outer rind is peeled back, revealing shredded, charcoal-colored internal tissue with tiny black microsclerotia (like black pepper sprinkled inside). Stalks become weak and lodge. Often appears after mid-season drought followed by rain during grain fill.
Conditions that favor it
Drought stress during post-flowering, followed by warm conditions. High plant populations and excessive nitrogen increase susceptibility. Sandy soils with low organic matter. The pathogen is soil-borne and persists as microsclerotia for years.
Grain Mold Complex
Fusarium, Aspergillus, Curvularia, Alternaria spp.
What you will see
Pink (Fusarium), green-yellow (Aspergillus), or black (Alternaria) fungal growth on mature grain in the head. Grain is discolored, shriveled, and may have visible fuzzy mold growth. Reduces grain quality, test weight, and may produce mycotoxins (aflatoxin, fumonisin).
Conditions that favor it
Rain and high humidity during grain maturity. Compact, tight heads retain moisture and favor mold. Insect damage (head bugs, earworm) provides entry points. Early-maturing varieties that escape late-season rains have lower mold incidence.
Anthracnose
Colletotrichum sublineolum
What you will see
Small, circular to elliptical spots on leaves with tan centers and dark red-purple borders. Severe infections cause premature leaf death from the bottom up. On the stalk: dark, sunken cankers. On the grain: dark, sunken lesions. Anthracnose stalk rot causes lodging.
Conditions that favor it
Warm (25-30°C), humid conditions with frequent rainfall. Most destructive in tropical and humid subtropical regions. Crop residue is the primary inoculum source. Race variation means resistant varieties can lose resistance over time.
Downy Mildew (Crazy Top)
Peronosclerospora sorghi
What you will see
White, downy fungal growth on leaf undersides (visible in early morning dew). Leaves develop alternating green and yellow-white stripes. Severely infected plants produce distorted, leafy heads ("crazy top") with no grain production. Systemic infection stunts the entire plant.
Conditions that favor it
Soil-borne oospores infect seedlings in cool, wet soils. Seed treatment with metalaxyl provides protection. Warm, humid mornings favor secondary spread from leaf spores.
Ergot (Sugary Disease)
Claviceps africana
What you will see
Sticky, honey-colored to pale yellow drops of honeydew oozing from unfertilized flowers on the head. The honeydew later hardens into dark, hard sclerotia (ergot bodies) that replace the grain. Infected heads have a characteristic wet, glistening appearance.
Conditions that favor it
Cool temperatures (below 20°C) during flowering that delay pollination, leaving flowers unfertilized and vulnerable. Male-sterile lines (used in hybrid production) are extremely susceptible because they depend entirely on wind-blown pollen from neighboring rows.
Common Sorghum Pests — Identification & Damage
Shoot Fly (Atherigona soccata)
Damage
The single most damaging early-season pest of sorghum in the Old World. The maggot cuts the growing point of the seedling, causing the classic "deadheart" symptom — the central leaf dies and can be pulled out. Yield losses of 50-90% occur in late-planted crops. Plants may produce side tillers but these yield poorly.
How to identify
Small (4-5mm), gray-brown fly that lays a single white, elongated egg on the underside of leaves. The maggot (5mm, cream-colored) is found inside the stem at the growing point. Look for deadhearts in seedlings 7-21 days after emergence. Early planting (within 1-2 weeks of the normal window) and resistant varieties are the best defenses.
Sorghum Midge (Contarinia sorghicola)
Damage
Tiny female flies lay eggs inside individual sorghum florets during anthesis. Larvae feed on the developing grain, replacing it with a hollow shell. A heavily infested head produces little to no grain while looking superficially normal until you rub the head and seeds crumble. Yield losses of 20-80% are common.
How to identify
Very small (2mm) orange-red flies visible on heads at dawn during flowering. Scout by gently tapping heads onto a white surface at sunrise. Staggered planting dates across a community concentrate midge populations on late-flowering fields. Threshold: 1 midge per head.
Fall Armyworm
Damage
Feeds on leaves in the whorl stage and on developing grain in the head stage. Whorl damage leaves ragged, shot-hole patterns on emerging leaves. Head-stage feeding damages developing grain directly. Yield losses of 15-40% in outbreak years. Same species that devastates corn.
How to identify
Same as in corn — larvae with inverted Y on head, four dark spots on last segment. Look for frass in the whorl. Threshold: larvae in 15% of plants during whorl stage. BT-based bioinsecticides are effective on small larvae.
Birds (Quelea, Weaverbirds, Sparrows)
Damage
The #1 constraint to sorghum production in Africa. Quelea quelea (red-billed quelea) forms flocks of millions that can strip entire fields in hours. Bird damage occurs from milk stage through maturity — birds puncture and consume developing grain. Yield losses of 30-100% are reported.
How to identify
Visible bird feeding damage — pecked, torn, and empty seed heads. Quelea flocks are unmistakable — dense clouds of birds that darken the sky. Sparrows and weaverbirds cause scattered damage. Bird-resistant varieties (with tannin or open panicles) help. Community-based bird scaring is essential.
Stalk Borer (Busseola fusca, Chilo partellus)
Damage
Larvae bore into stalks, causing deadhearts in young plants and stalk breakage in older plants. Tunneling in the peduncle (the stalk below the head) disrupts grain fill, producing lightweight, shriveled grain. Multiple larvae per stalk compound the damage.
How to identify
Cream to pink larvae (25-35mm) with dark head capsules, found inside the stem. Entry holes visible on the stem with frass pushed out. Dead hearts in the vegetative stage. Weak, broken peduncles during grain fill. Cut stalks open to find larvae and assess damage.
Sorghum Nutrient Management — NPK Guide
Nitrogen (N)
60-80 lb N/acre (moderate user — sorghum is relatively efficient)
Phosphorus (P)
25-40 lb P2O5/acre
Potassium (K)
20-40 lb K2O/acre
Application Timing
Apply 30-40 lb N/acre at planting or soon after emergence. Side-dress remaining N at the 5-6 leaf stage (before boot). Excessive nitrogen increases susceptibility to charcoal rot and promotes vegetative growth at the expense of grain. In Africa, even 20-30 lb N/acre dramatically improves yields over unfertilized sorghum.
Sorghum Irrigation Schedule
Total Water Requirement
16-24 inches (400-600mm) — but sorghum survives on as little as 12 inches (300mm)
Critical Stages
Boot stage through flowering is the most water-sensitive period. Sorghum can go dormant during vegetative drought and resume growth later — this is its unique advantage. Post-flowering drought triggers charcoal rot but sorghum still produces some grain.
Irrigation Frequency
90% of global sorghum is rainfed. If irrigating, focus on boot through grain fill (2-3 irrigations of 3-4 inches). Sorghum's deep root system (up to 6 feet) accesses subsoil moisture that other crops cannot reach.
Sorghum Economics — Cost, Yield & Profit
Cost per Acre
$250-400/acre (US); $50-150/acre (African smallholder)
Yield per Acre
75-120 bushels/acre (US irrigated); 800-2,000 lb (African smallholder)
Revenue per Acre
$375-600/acre (US at $5-6/bushel)
Profit per Acre
$50-200/acre
Regional Context
Sorghum competes with corn for acreage in the US, and is chosen when water is limited (western Kansas, Texas Panhandle). In Africa, sorghum is a food security crop with limited commercial market development. Sorghum is the primary grain for gluten-free beer and food products, commanding premiums in specialty markets. Ethanol production from grain sorghum is growing. Sweet sorghum varieties produce both grain and fermentable stalk juice for biofuel.
Frequently Asked Questions — Sorghum Farming
Why is sorghum more drought-tolerant than corn?
Sorghum has multiple drought-survival mechanisms that corn lacks: (1) A waxy bloom on leaves and stems that reduces water loss by 15-25%, (2) A more extensive and deeper root system — sorghum roots reach 6+ feet deep versus 4 feet for corn, accessing subsoil moisture, (3) The ability to go dormant during drought and resume growth when water returns (corn cannot do this — once stressed, yield loss is permanent), (4) Smaller leaf area per plant that reduces transpiration demand, (5) Osmotic adjustment — sorghum cells accumulate solutes to maintain turgor at lower water potentials, (6) Higher water use efficiency — sorghum produces more grain per unit of water consumed. These traits make sorghum the ideal cereal for regions receiving 300-600mm of rainfall where corn would fail.
How do I manage bird damage in sorghum?
Bird damage is the single biggest challenge for sorghum farmers in Africa, with quelea flocks capable of destroying entire fields. Management strategies include: (1) Plant bird-resistant varieties — those with high tannin content (birds dislike the bitter taste) or open, loose panicles (harder for birds to perch on), (2) Synchronize planting across the community so all fields mature at the same time, spreading bird pressure rather than concentrating it on early or late fields, (3) Bird scaring — noise, reflective tape, and human presence during the milk-to-maturity stage (4-6 weeks of daily effort), (4) Plant tall varieties — birds prefer short sorghum they can reach from the ground, (5) Harvest early (at 18-20% moisture) and dry off-field, (6) In severe quelea areas, some farmers are shifting to bitter-grain sorghum varieties for human food (tannin is removed by traditional processing) or sweet sorghum for dual purpose.
Can sorghum be used for gluten-free products?
Yes — sorghum is naturally 100% gluten-free, making it an increasingly valuable crop for the growing gluten-free food market. Sorghum flour can replace wheat flour in many applications: flatbreads, porridges, couscous, pancakes, and baked goods. White-grain sorghum varieties are preferred for food products (no tannin, mild flavor). In the US, sorghum is now used in gluten-free beer (major craft breweries use 100% sorghum), cereals, snack foods, and flour blends. Sorghum syrup (from sweet sorghum) is a traditional sweetener in the US South. The global gluten-free market is growing at 9% annually, and sorghum is positioned to capture significant share as awareness increases.
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