🌿 Cassava Farming and Processing

What this course covers

12 modules · 72 written lessons · about 51,270 words · 360 quiz questions · 12 capstone projects.

Every lesson has learning objectives, worked numbers, a "do this today" task and a knowledge check. Videos are free material made by other people; the written lessons are the course.

The Business of Cassava

Cassava is two businesses wearing one plant: a household food-security crop that can be left standing in the ground for a year, and an industrial raw material that feeds bakeries, starch factories and feed millers. This module covers why cassava produces more food energy per hectare than the cereals around it, who actually buys cassava and in what form, why a root that keeps for a year in the soil rots in three days in a sack, and how to build a costing on your own local prices because no reliable current African price exists to give you. It ends with the yield gap, and how to read any yield figure anyone quotes at you.

1. Why Cassava Feeds Africa
2. Two Businesses Under One Crop
3. The 48 to 72 Hour Clock
4. Who Actually Buys Cassava
5. Costing a Cassava Business Without a Price
6. Reading a Yield Figure Before You Trust It

Open module 1 →

The Cassava Plant

Everything you will do to a cassava field, and everything you must do to a cassava root after you dig it, comes from how this particular plant works. This module covers the plant's basic botany, the growth stages from sprouting to canopy closure to root bulking, why it produces on acid and exhausted soils that defeat maize, why it survives drought, and why it contains cyanogenic compounds at all. Understanding the mechanism is what lets you adapt when your variety, your soil or your season is not the one in the book.

1. What Kind of Plant You Are Growing
2. From Cutting to Closed Canopy
3. How the Root Fills and When It Is Ready
4. Why Cassava Produces on Tired Soil
5. Why Cassava Survives Drought
6. Cyanogenesis: The Plant's Own Defence

Open module 2 →

Choosing Varieties

Variety choice is the first decision you make and the hardest one to undo, because a cassava field is planted for nine to twenty-four months and the stems you plant become the stems you plant again. This module covers the sweet and bitter distinction as the safety line it actually is, what one sourced Ugandan study measured across twelve local and improved varieties, why disease resistance is a moving target rather than a permanent property, and how to match a variety to the market you are actually selling into.

1. Sweet and Bitter Is a Safety Line
2. What the Ugandan Variety Study Found
3. Improved Varieties and Local Varieties
4. Disease Resistance Is a Moving Target
5. Matching the Variety to Your Market
6. Getting a Current Recommendation and Testing It Yourself

Open module 3 →

Planting Material

Cassava has no seed system, and almost everything difficult about the crop follows from that one fact. This module covers how to select and cut good stakes, why moisture loss is the thing that kills them, what treatment can and cannot do, and the multiplication arithmetic that limits how fast any cassava farmer or seed enterprise can grow. It also shows why clean planting material is the highest-leverage disease-control action available to a smallholder.

1. Why Cassava Has No Seed System
2. Cutting a Good Stake
3. Keeping Cuttings Alive
4. Treating Cuttings Before Planting
5. The Multiplication Problem
6. Rapid Multiplication and the Clean-Seed Business

Open module 4 →

Land Preparation, Spacing and Intercropping

Everything you decide before the first stake goes in the ground is decided for the whole cycle, because you cannot respace a cassava field at month six. This module covers land preparation as the first step of weed control rather than a separate job, ridges versus flat planting, the reported planting angles and depths, plant population arithmetic, and how to intercrop cassava without quietly paying for the companion crop out of your root yield.

1. Land Preparation Is Weed Control
2. Ridges, Mounds or Flat
3. Planting Angle and Depth
4. Spacing and Plant Population
5. Intercropping Without Paying for It
6. Planning and Running Planting Day

Open module 5 →

Soil Fertility and Weed Control

Cassava has a reputation for growing where nothing else will, and that reputation quietly costs farmers their land. This module gives you the sourced figures for what a cassava crop removes from the soil, shows you honestly where those figures disagree with each other, and turns the potassium trial evidence into a fertiliser decision you can actually make. It then covers the critical weed-free period, the reported cost of getting it wrong, and how to build one written fertility and weeding plan for one field.

1. What A Cassava Crop Takes Out
2. Tolerant Of Poor Land, And Mining It
3. Putting Fertility Back
4. The Critical Weed-Free Period
5. Weeding Methods And What They Cost
6. One Field, One Written Plan

Open module 6 →

The Two Virus Diseases That Decide Your Crop

Cassava mosaic disease and cassava brown streak disease are the two biggest biological threats to an African cassava business, and both of them travel in the stem cuttings farmers give each other. This module teaches how each one spreads, what the published loss figures actually measure, and why clean planting material and rogueing are the only tools a grower has against a virus. It also teaches you to read a loss figure critically before you build a plan on it.

1. How Cassava Mosaic Disease Moves
2. Brown Streak: The Loss You Cannot See
3. Clean Planting Material Is the Whole Battle
4. Rogueing, Sanitation and Slowing the Spread
5. Choosing a Variety Without Being Sold a Story
6. Planning for Pressure That Is Rising, Not Falling

Open module 7 →

Insects, Mites and the Diseases You Can Still Beat

This module covers the cassava mealybug, the cassava green mite, cassava bacterial blight and cassava anthracnose, and the reason they belong together is that they show the two very different faces of crop protection. Two of them were solved across a continent by releasing a natural enemy, in one of the best-documented returns on investment in the history of agriculture. The other two still depend on what you personally do with your cuttings, your knife and your rotation. Knowing which kind of problem you have decides which tools even exist.

1. The Mealybug That Nearly Took the Crop
2. The Wasp That Paid Back Hundreds to One
3. Green Mite and the Second Release Programme
4. Cassava Bacterial Blight and the Cost of a Dirty Knife
5. Anthracnose, Wounds and Planting Material Viability
6. Matching the Tool to the Problem

Open module 8 →

Harvesting: Timing, Lifting and What the Yield Really Is

Cassava is the only major staple that lets you choose your own harvest date across a window of months rather than forcing you to cut on a fixed calendar. This module teaches how to decide when to lift, how to lift without breaking roots, how to measure what your own field actually yields instead of trusting a number somebody quoted you, and how the manual versus mechanised choice changes both your labour bill and your per-tonne cost. Harvest is also the moment the crop stops being safe in the ground and starts being perishable, which is why it decides everything in the next module.

1. Choosing Your Harvest Date
2. Test Digging and Measuring Your Own Yield
3. Reading a Yield Figure Before You Believe It
4. Lifting Roots Without Breaking Them
5. Manual Versus Mechanised Lifting
6. Planning the Harvest Day

Open module 9 →

The 72-Hour Problem: Why Cassava Roots Spoil So Fast

A cassava root can wait safely in the ground for a year and then spoil in a sack in three days. That contradiction is the single most important commercial fact about the crop, and it explains why cassava has never become an internationally traded fresh commodity and why processing, not growing, is where a cassava business succeeds or fails. This module teaches what post-harvest physiological deterioration actually is, how fast it moves, why it varies so much between varieties, what genuinely slows it, and how to run a business around a clock that starts the moment a root leaves the soil.

1. The Clock That Starts at Lifting
2. How Much It Varies: 24 Hours to 11 Days
3. What Is Happening Inside the Root
4. Wound Healing, the Periderm and a Counter-Intuitive Finding
5. What Actually Slows Deterioration Down
6. Running a Business Against the Clock

Open module 10 →

Processing and Cyanide Safety

Cassava contains cyanogenic glucosides as a chemical defence, and badly processed bitter cassava has killed people and left others permanently paralysed by konzo. This module teaches the two mechanisms by which processing removes cyanide, then walks through gari, fufu, chips, starch and high-quality cassava flour showing what each step is actually doing chemically. It is written so that you can tell when a step has gone wrong, not merely follow a recipe, because no time or temperature in this course is a guarantee of safety for your own roots.

1. The Poison in the Plant and the Disease It Causes
2. The Two Mechanisms That Remove Cyanide
3. Gari: Every Step and What It Is For
4. Fufu, Chips and Why Chains Beat Single Steps
5. Starch and High-Quality Cassava Flour
6. Knowing When a Step Has Gone Wrong

Open module 11 →

Value Addition, Markets and Costing

Capacity to grow cassava is rarely the scarce resource. Capacity to process it fast, safely and to a consistent standard is. This final module covers who actually buys cassava products, how to choose which product your own operation should make, how to calculate a break-even price from your own costs rather than trusting a quoted price, and which records turn a cassava operation into a business that knows whether it is making money.

1. Where the Value Actually Sits
2. Who Actually Buys Cassava
3. Choosing Which Product to Make
4. Working Out Your Break-Even Price
5. The Records That Make It a Business
6. Putting the Whole Course to Work

Open module 12 →