Cassava, or kamoteng kahoy, is one of the most versatile and resilient crops a Filipino farmer can grow. It tolerates poor soils, irregular rainfall, and the kind of marginal land that other commercial crops cannot handle. At the same time, it feeds over 500 million people worldwide, supplies a growing starch and bioethanol industry, and has earned a permanent spot in the Philippine government's Food Staples Sufficiency Program as a viable alternative to rice. This guide merges all three original Juan Magsasaka cassava production articles into one complete, updated resource covering the entire production cycle from site selection to post-harvest processing.
📋 Table of Contents
- Why Grow Cassava: Economic and Nutritional Value
- Site Selection: What Cassava Needs to Thrive
- Land Preparation
- Selecting and Preparing Planting Materials (Stakes)
- Planting Cassava: Spacing, Depth, and Position
- Fertilizer Application and Soil Fertility Management
- Weed Management
- Harvest: When and How to Dig Cassava
- Post-harvest Handling, Processing, and Storage
- Cost and Return Analysis
- Frequently Asked Questions
1Why Grow Cassava: Economic and Nutritional Value
Cassava (Manihot esculenta Crantz) goes by many names in the Philippines. Kamoteng kahoy is the most common, but you will also hear balanghoy in the Visayas and pagi in parts of Mindanao. Whatever you call it, the crop has a long track record as a food source, a feed ingredient, an industrial raw material, and increasingly, an ethanol feedstock. The demand from starch processors and bioethanol plants has grown significantly in recent years, which is why the DA included cassava under the Agri-Pinoy Corn Program and the Food Staples Sufficiency Program.
From a nutrition standpoint, cassava roots are rich in starch and provide meaningful amounts of calcium, iron, phosphorus, dietary fiber, manganese, potassium, vitamin B6, and vitamin C. Research from Philippine institutions has found that high total dietary fiber content in cassava may help lower cholesterol and triglyceride levels. The crop has also been used in traditional medicine for managing conditions ranging from rheumatism and fever to digestive complaints.
From a commercial standpoint, cassava has two major market channels for Philippine farmers. The first is the fresh root market, which includes wet markets, restaurants, and food processors who need raw roots for local food products. The second, and more scalable channel, is the dried chips or granules market, which feeds into the starch, flour, and animal feeds industries. Contract growing arrangements with processors are available in many provinces and provide guaranteed off-take at agreed prices, which reduces the price uncertainty that plagues most vegetable crops.
2Site Selection: What Cassava Needs to Thrive
Cassava is often described as a forgiving crop, and in many ways it is. It can grow where other crops fail. But forgiving does not mean indifferent. The right site makes a significant difference between a 20-tonne harvest and a 60-tonne harvest on the same area of land. Here are the key factors to evaluate before committing to a site.
An open, flat to gently sloping field with good drainage is ideal for commercial cassava production.
Climate
Cassava is a tropical and subtropical plant that does best in regions with rainfall distributed fairly evenly throughout the year. It grows well between 25 and 30 degrees Celsius and can be farmed from sea level up to about 845 meters above sea level. The single most important weather-related decision you make is timing: plant at the start of the rainy season so that the young plant has adequate moisture during its critical first three months. Drought stress in this period significantly reduces root yield and produces deformed roots.
Slope and Topography
Flat or gently undulating land with a slope of no more than 15 percent is ideal. Steeper slopes are not impossible to farm, but they require water and soil conservation measures. The most practical approach for sloping land in the Philippines is the Sloping Agricultural Land Technology (SALT), which uses contour hedgerows of nitrogen-fixing shrubs like ipil-ipil or madre de cacao to slow erosion and improve soil organic matter over time.
Soil Type and pH
Cassava grows best in sandy loam to clay loam soil. It tolerates lower pH than most crops (as low as 5.5 is acceptable, with an ideal range of 5.5 to 6.5), tolerates elevated levels of soluble aluminum, and can manage with low available phosphorus better than other root crops. This makes it a natural fit for upland areas that have been degraded by previous farming or erosion.
Drainage
This is the non-negotiable. Cassava cannot tolerate waterlogging for more than 24 hours. Young plants (1 to 3 months old) will become stunted. Mature plants will develop rotten roots if the soil stays saturated. If your target field has a history of flooding or has heavy clay subsoil that drains poorly, either choose a different site or invest in raised beds and drainage canals before planting.
3Land Preparation
Good land preparation creates the loose, well-aerated soil environment that cassava roots need to expand laterally and develop the bulky, uniform tubers that command better prices at the weighbridge. Skipping steps here typically results in stunted root development and uneven stands.
- First plow: Plow to a depth of at least 15 cm (6 inches). Deeper is better for cassava since the roots need room to expand downward. Do this when the soil has adequate moisture. A common field test: squeeze a handful of soil. If it holds a shape briefly and then crumbles, the moisture is right for tillage.
- Second plow: A second pass breaks remaining clods, exposes weed seeds and soil pests to sun and desiccation, and leaves a more uniform seedbed. For fields with heavy weed pressure or previous crop residues, this pass is especially important.
- Harrowing: Harrow twice to pulverize the soil surface, level the field, and prepare a fine-textured seedbed that gives the cutting direct soil contact for faster sprouting.
These operations should always be done when there is enough soil moisture but not when the soil is wet and sticky, which would compact the field under equipment weight and undo the aeration benefits of plowing.
4Selecting and Preparing Planting Materials (Stakes)
Unlike most vegetable crops, cassava is not grown from seed. It is propagated from stem cuttings, locally called stakes or seed pieces. The quality of your planting material is one of the most important factors in final yield. Poor-quality stakes sprout unevenly, produce weak plants, and increase replanting labor and cost. Getting this right from the start saves significant work down the line.
Healthy stakes cut from mature stems produce more uniform stands and higher root yields.
What Makes a Good Stake
A planting stake must meet three criteria simultaneously: it must be mature, fresh, and healthy.
- Mature: The diameter of the pith (the soft inner core) should not exceed half the diameter of the cortex (the outer layer). Stems from overly young plants have a proportionally large pith, which produces weaker sprouts.
- Fresh: When you cut the stem, latex or sap should appear at the cut surface within 3 seconds. Delayed or absent sap flow signals a dehydrated or dead stem that will not sprout reliably.
- Healthy: The stem must be free of visible insect damage, disease lesions, and discoloration. The minimum stem diameter is 1.5 cm. Undersized stems lack the stored energy needed for vigorous sprouting.
Cross-section of a cassava stem. A mature stem has pith diameter no larger than half the cortex diameter.
Cutting and Storing Stakes
- Cut stems using a sharp bolo to produce clean, smooth cuts that do not crush or fray the nodes. Crushed nodes sprout poorly.
- Cut each stake 15 to 30 cm long. Each stake must have at least 7 viable nodes (the small, slightly raised rings along the stem where buds will sprout).
- Handle cuttings gently. Do not throw, drop, or drag them. Damaged nodes fail to sprout.
- If you cannot plant immediately, store the stakes in a cool, shady location with the base ends (the end closer to the soil) facing downward. This orientation helps maintain moisture balance in the stem. Proper storage allows stakes to remain viable for up to one month.
Stakes stored upright in a shaded area maintain viability for up to one month before planting.
5Planting Cassava: Spacing, Depth, and Position
Planting technique has a direct and measurable impact on stand establishment. The right spacing, planting depth, and stake orientation determine how uniformly and vigorously the crop establishes, which in turn affects how much root mass you harvest per hectare.
Making the Planting Ridges
Before planting, construct ridges 15 to 20 cm high. Space the ridges 75 to 100 cm apart. Ridges serve two purposes: they provide the loose, elevated soil mass that cassava roots need to expand freely, and they also improve drainage around the root zone. This is especially important during the wet season when saturated conditions can cause early root rot.
Ridges 15 to 20 cm high provide the loose soil environment cassava roots need to expand properly.
Planting Position
Stakes can be planted in vertical, slanting, or horizontal positions. Each has tradeoffs.
| Planting Position | Description | Best For | Notes |
|---|---|---|---|
| Vertical | Stake inserted straight up; bury 2/3 of length (3–5 nodes underground) | Most Philippine conditions | Most reliable; produces well-anchored plants |
| Slanting | Stake inserted at an angle; same burial depth as vertical | Rocky or difficult soils | Easier to insert in hard soils; slightly more prone to leaning |
| Horizontal | Stake laid flat in a shallow trench, fully covered | Dry areas; mechanized planting | Slower to emerge; roots tend to spread laterally (good for harvesting) |
Vertical planting is the most reliable for Philippine conditions. Ensure the stake remains upright after covering.
Plant Spacing
Plant one cutting per hill, with 50 to 75 cm between hills within the row and 75 to 100 cm between rows. This gives each plant enough space to develop a full root system without crowding. At 75 cm x 100 cm spacing, you will have approximately 13,000 plants per hectare.
After Planting
Check the stand 2 to 3 weeks after planting and replant any hills where the stake failed to sprout. Early replanting of dead hills is critical because late replacements will remain smaller than the rest of the crop throughout the season, reducing per-plant yield in those spots. Also, 3 to 4 weeks after planting, remove any weak or diseased sprouts at each hill, leaving only the single strongest, healthiest plant per hill.
6Fertilizer Application and Soil Fertility Management
Cassava has a reputation for being manageable in poor soils, and this is true. But that does not mean it ignores fertilizer. The crop removes substantial amounts of nitrogen, phosphorus, potassium, calcium, and magnesium from the soil with every harvest. If you grow cassava on the same land season after season without replenishing these nutrients, soil productivity will decline predictably until yields become uneconomical. Fertilizing cassava is not optional; it is soil insurance.
Proper fertilization produces uniform plant height and canopy closure, which also helps suppress weeds.
What Cassava Takes from the Soil
At a yield of 20 tonnes of fresh roots per hectare, cassava removes approximately 54 kg of nitrogen, 11 kg of phosphorus (P2O5), and 76 kg of potassium (K2O). Higher-yielding crops remove proportionally more. Continuous cropping without replacement of these nutrients is the most common reason for yield decline on established cassava farms.
Inorganic Fertilizer Recommendation
If you have not done a soil test (which is the recommended starting point), the general DA recommendation for Philippine conditions is 8 bags (400 kg) of complete fertilizer (14-14-14) per hectare.
- Apply 2 to 6 weeks after planting, not at planting. Newly inserted stakes have not yet developed roots capable of absorbing fertilizer, so applying too early wastes inputs and can burn emerging root tips.
- Apply at 5 to 10 cm depth and 15 to 20 cm away from the base of the plant. On flat land, open a shallow canal beside the plant row using a plow, apply the fertilizer, and cover immediately with soil. Do not leave fertilizer exposed on the soil surface, as it evaporates and washes away in rain.
- On sloping land, dibble the fertilizer (push it into a small hole) 3 to 5 cm from the plant base and cover with soil to prevent runoff loss.
Organic Fertilizer
The DA recommends supplying at least 30 percent of the total nutrient requirement through organic sources, whether that is composted manure, commercially processed organic fertilizer, or compost you produce from crop residues. Organic matter improves soil structure, water retention, and microbial activity, all of which benefit cassava root expansion and overall soil health across successive crops.
The most cost-effective source of organic matter for a cassava farm is the cassava plant itself. After harvest, gather the stems, leaves, and peelings in one area to decompose. The resulting compost can be applied as mulch in the next cropping season or incorporated during land preparation. This closed-loop approach reduces purchased input costs season by season.
7Weed Management
Weeds are one of the most consistent productivity reducers in cassava farming, especially during the first three months when the crop canopy has not yet closed and sunlight reaches the soil between plants. Unmanaged weeds in this critical early period can reduce cassava yields by 50 percent or more in severe cases. Once the cassava canopy closes (usually by 3 to 4 months), natural shading suppresses most weeds without additional intervention.
How Weeds Spread in Cassava Fields
Annual weeds reproduce primarily through seeds that can remain viable in the soil for several years. These seeds wait dormant until soil disturbance (plowing and harrowing) brings them near the surface, where they germinate rapidly. The best defense against annual weeds is to remove them before they flower and set seed, which interrupts the cycle and reduces the weed seed bank in your soil over successive seasons.
Perennial weeds like bermuda grass (Cynodon dactylon) spread through vegetative structures. Cutting or chopping these weeds during land preparation creates fragments that each sprout into a new plant, which is why bermuda grass pressure often intensifies immediately after plowing. The key for perennial weeds is mechanical removal of the root mass, not just cutting the above-ground parts.
Weed Control Schedule
- 13 to 4 weeks after planting: Off-barUse an animal-drawn plow or hand tools to loosen the soil between rows (off-barring). This uproots germinating weed seedlings before they establish and also aerates the root zone, which encourages early cassava root development.
- 24 to 5 weeks after planting: Hand-weed within rowsThe plow cannot reach weeds between plants in the same row without damaging the cassava roots. Hand-pull or cut weeds within the rows at this stage. Focus on removing weeds that are large enough to compete for nutrients but have not yet flowered.
- 3By 3 months after planting: Hill-up after side-dressingAfter applying sidedress fertilizer, hill up the soil around the base of each plant. Hilling covers the fertilizer, protects root tips, and buries small weeds that may have germinated in the row. Do this no later than 3 months after planting, as hilling after this point risks damaging the expanding root system.
8Harvest: When and How to Dig Cassava
Timing and technique both matter enormously at harvest. Harvest too early and you sacrifice yield and starch content. Harvest too late and roots become woody, fibrous, and prone to damage from underground pests. Handle roots carelessly and you induce the rapid deterioration that makes cassava one of the most challenging post-harvest crops in Philippine agriculture.
Proper harvest technique minimizes root damage and extends the usable life of the roots after digging.
Optimal Harvest Timing
The right harvest window depends on your intended market.
- Fresh root market (food): Harvest at 6 to 7 months after planting. At this stage, roots have developed good size and eating quality but have not yet become fibrous.
- Starch and flour processing: Harvest between 10 and 12 months, when starch content peaks. Tubers for flour or starch should be no older than 16 months; beyond this, they become too fibrous to process efficiently.
- Dried chips and contract growing: Most processors specify 9 to 12 months. Confirm the target age with your buyer before scheduling harvest.
Harvest Conditions and Technique
- Do not harvest immediately after heavy rain. Roots have high water content in wet conditions, which reduces their dry weight and makes them harder to clean. Wet clay soil also sticks to roots and complicates processing. Wait for dry weather.
- Harvest only what you can process or sell within 2 days. Unlike most crops, cassava cannot be staged in the field after cutting without losing quality. Once separated from the plant, the roots begin deteriorating within 24 to 72 hours under ambient Philippine conditions.
- Loosen compacted soil before pulling. If the soil is hard, loosen it with a wooden stake or digging bar before pulling. Metal tools cause more root damage than wooden ones. Pull the plant gently and avoid dragging the roots, which creates bruises that accelerate deterioration.
- Separate roots using a sharp bolo, not by breaking. Cut each root as close to the stem as possible. Breaking roots off by force leaves jagged wounds that deteriorate faster than clean cuts.
- Process damaged and small roots first. Sort immediately after digging. Damaged, bruised, or undersized roots deteriorate faster and should be processed before larger, intact ones.
- Do not leave roots under direct sun. Heat causes rapid weight loss and surface deterioration. Move roots into shade immediately after pulling.
9Post-harvest Handling, Processing, and Storage
Post-harvest handling is where many small-scale cassava farmers lose significant value. Understanding your processing options and their quality requirements directly affects how much you can charge for the output and how much of your harvest you can successfully market.
Processing Options Overview
Each step up the value chain requires more labor and equipment but produces a more valuable, more storable product. Dried chips are the most accessible processing option for most Philippine smallholder farmers and the most common form for contract delivery.
Pre-drying
Sun-dry freshly harvested, uncleaned roots for up to 4 hours. This surface drying makes it much easier to remove adhering soil particles before processing, particularly in fields with heavy clay soils.
Processing Dried Chips
- Wash roots thoroughly with clean water to remove all soil, sand, and foreign matter. Contaminated chips result in a lower quality grade and price deductions from processors.
- For starch or flour production, peel the roots using a sharp knife or bolo. Roots for animal feed processing do not need peeling.
- Cut or chip roots into slices not more than 5 mm thick (approximately 3/8 inch). Thinner chips dry faster and more uniformly. Chipping can be done manually with a sharp bolo or using a mechanical chipper for larger volumes.
- Lay bamboo or woven mats on flat ground fully exposed to sunlight. Spread chips evenly, not more than 7 cm (3 inches) thick, for uniform drying.
- Sun-dry for 2 to 3 days until chips reach 14% moisture content or lower. Test dryness by trying to bend a chip: properly dried chips snap cleanly rather than bending.
- In areas with frequent rain, use a plastic roof shed with an elevated, ventilated floor for the first 1 to 2 days of drying, then transfer to a mechanical dryer if available.
Granulation (Value-Added Option)
Fresh roots can also be processed into granules (roughly 8 to 10 mm pieces) using a cassava granulator instead of slicing into chips. Granules require a shorter drying period than chips, fetch a slightly higher price from some buyers, and are less bulky and easier to transport. If a granulator is accessible in your area, this is worth considering for commercial-scale production.
Storing Dried Chips and Granules
Pack dried chips or granules in clean laminated sacks or polypropylene sacks and tie tightly. Store in a dry, shaded, and well-ventilated area. Elevate sacks from the floor using wooden pallets to prevent moisture absorption from the ground. Do not dry chips or granules in sandy areas, where fine particles contaminate the product and lower its quality grade.
Root Storage (Without Processing)
If you need to hold fresh roots before processing for a few days to weeks without ambient refrigeration, soil storage is the traditional method. Select a well-drained, shaded, and slightly sloping site. Dig trenches 1 meter wide and 30 to 40 cm deep. A 1-meter trench holds approximately 70 to 80 kg of roots. Line each layer of roots with river sand or sea sand rather than heavy clay, which promotes root decay. Make a drainage canal at the downhill end of each trench to carry away moisture.
Producing Cassava Flour and Starch
Flour and starch production requires tubers that are not overly fibrous, ideally from plants 10 to 12 months old and harvested no more than 16 months after planting. Roots must be processed within 24 hours of harvest for best starch yield.
- Wash, peel, and re-wash tubers after peeling to remove latex residue.
- Slice thinly or shred using a papaya shredder or mechanical grater.
- Soak or wash the shredded cassava in enough clean water to partially remove the starch. Allow the starch to settle at the bottom of the container.
- Drain the shredded cassava. Spread in a sieve or basket lined with sinamay cloth and sun-dry until crisp and brittle.
- Grind the dried cassava through a cornmeal grinder and pass through a No. 120-mesh sieve. The output is cassava flour. Pack in airtight containers, preferably sealed plastic bags.
- The water drained in step 3 contains cassava starch suspended at the bottom. Carefully pour off the clear water (decanting), then sun-dry the settled starch completely. Pack the dried starch in sealed, moisture-proof containers.
10Cost and Return Analysis
The following figures are adapted from the DA-NOMIARC cost and return analysis for a 1-hectare cassava farm using the Rayong variety, which is known for its high yield potential. These figures are for reference and context. Input costs and farmgate prices have changed since 2013, so treat this as a structural guide rather than a current estimate. Always obtain current input prices from your local agricultural supply and compare with your nearest processor's current buying price before committing to a new season.
| Item | Amount | Notes |
|---|---|---|
| Fresh Root Yield | 60,000 kg/ha | Rayong variety under good management |
| Dried Chip Conversion | 28,200 kg | Roughly 47% conversion rate from fresh root |
| Selling Price (chips) | P8.00/kg | DA-NOMIARC 2013 basis; current contract prices are P11–P15/kg |
| Gross Income | P225,600 | Based on 28,200 kg x P8 |
| Total Expenses | P68,860 | Includes labor, inputs, land prep, and transport |
| Net Income | P156,740 | Per hectare per crop season |
11Frequently Asked Questions About Cassava Farming
When is the best time to plant cassava in the Philippines?
The best time is at the start of the rainy season, typically May to June in most Philippine regions. Adequate soil moisture during the first three months after planting is critical for good root development. Planting without reliable moisture during this period leads to deformed roots and low yields.
How long does cassava take to mature?
Cassava matures between 6 and 12 months after planting, depending on the variety and your intended market. For fresh consumption, 6 to 7 months is the target. For starch extraction and industrial processing, 10 to 12 months produces the highest starch content. Do not leave roots in the ground past 16 to 18 months, as they become fibrous and lose processing value.
What is the recommended fertilizer for cassava?
The general recommendation for unanalyzed Philippine soils is 8 bags (400 kg) of complete 14-14-14 fertilizer per hectare, applied 2 to 6 weeks after planting at 5 to 10 cm depth and 15 to 20 cm from each plant. Always pair inorganic fertilizer with organic matter, supplying at least 30 percent of the crop's nutrient needs through compost or manure. Conduct a soil test for more accurate recommendations tailored to your field.
How do I know if my cassava stakes are good for planting?
Good stakes must be mature (pith no larger than half the cortex), fresh (latex appears within 3 seconds of cutting), and healthy (no pests or disease signs; stem diameter at least 1.5 cm). Stakes should be 15 to 30 cm long with at least 7 nodes. Handle gently to protect the nodes where sprouting occurs.
How do I store fresh cassava roots after harvest?
Fresh cassava roots are extremely perishable. Under ambient Philippine conditions, they begin deteriorating within 1 to 3 days. For short-term holding, use soil trenches covered with river sand. For longer storage, process roots into dried chips or granules at 14% moisture or lower, pack in clean laminated sacks, and store elevated on wooden pallets in a dry, shaded, well-ventilated area.
Can cassava farming be profitable through contract growing?
Yes. Contract growing with starch processors or trading companies provides a guaranteed off-take and removes the price uncertainty of the open market. Reported contract prices for dried cassava chips have been P11 to P15 per kilo. Some processors also provide planting materials and fertilizer under a credit arrangement recovered at harvest. The key is to confirm current prices and terms with your local processor before committing to a planting season.
Does the site selection guide apply to all cassava varieties?
The general site requirements apply to all commonly grown Philippine varieties. However, specific varieties may differ in their tolerance to acidic soils, drought, or waterlogging. When selecting a variety for contract growing, always confirm with your buyer which variety they accept, as starch content and dry matter yield vary significantly between varieties. Your local DA extension office can also recommend locally adapted varieties for your province.
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