GRADE 9 Agriculture FOOD PRODUCTION PROCESSES – STORAGE OF CROP PRODUCE Notes

What is storage of crop produce?

Storage of crop produce means keeping harvested crops (maize, beans, potatoes, rice, onions, etc.) in a safe place so they stay good for later use or sale. Good storage reduces losses from pests, moisture and moulds.

Why storage is important

• Keeps food safe for home use and sale.
• Prevents grain spoilage and reduces financial loss.
• Helps manage food supply between harvests.
• Reduces risk of aflatoxin (dangerous mould) in maize when kept dry.

Basic principles of good storage

1. Cleanliness: Store only clean, sound grain. Remove broken seeds, stones and plant debris.
2. Dryness: Keep moisture low. Dry crops before storage to safe moisture content (see table below).
3. Protection from pests: Prevent insects, rodents and birds from reaching the produce.
4. Ventilation: Allow air to move to avoid hot spots and condensation.
5. Temperature control: Cooler and stable temperature slows spoilage.

Safe moisture levels (approx.)

• Maize: about 12–13% — wet maize grows moulds and aflatoxin.
• Beans: about 12–13%.
• Rice: about 13–14%.
• Wheat & sorghum: about 12–13%.
• Potatoes: store at cool, dark, ventilated place (do not store wet potatoes).

Tip: Use a moisture meter if available. If not, sun-dry until grains feel hard when bitten.

Common storage methods used in Kenya

Pests and spoilage to watch for

• Insect pests: weevils and grain borers (look for holes and fine dust).
• Rodents: rats and mice (look for droppings and chewed bags).
• Moulds and aflatoxins: caused by damp storage. Aflatoxin can make people and animals very sick.
• Sprouting and rotting: common in tubers (potatoes, sweet potatoes) if too warm or wet.

Safe storage practices (easy checklist)

• Harvest at the right time — avoid damaged or unripe crops.
• Dry crops fully before storage — use tarpaulins and raise produce off the ground.
• Clean and repair storage structures — fix holes and cracks.
• Use strong sacks, sealed bags or metal containers for small storage.
• Keep storage areas cool, dark and ventilated.
• Inspect weekly for pests, damp spots or heating.
• Do not store wet or mouldy grain with clean grain.
• If chemical pesticides are needed, have a trained extension officer advise and supervise.

How to dry grain simply

1. Spread grain thinly on clean tarpaulin or concrete floor in the sun ☀️.
2. Stir often so grain dries evenly.
3. Bring in at night or during rain.
4. Check by biting a grain — it should be hard and not pastey.

Safety and environment

Use pesticides only when necessary and under expert guidance. Avoid eating mouldy grain — it can poison people and animals. Prefer safe methods like drying and hermetic storage whenever possible.

Classroom activity (10–20 minutes)

Ask learners to work in small groups and make a simple storage plan for a small farm that grows maize and beans. They should list:

• Steps from harvest to store (3–6 steps).
• One low-cost pest control idea (e.g. hermetic bag, raised granary).
• How to check moisture without a meter.

Key terms (short)

Hermetic: airtight, so no air gets in or out.

Threshing: separating grain from the chaff and stalks.

Aflatoxin: harmful poison produced by some moulds in wet grain.

Local tip: Visit your county agricultural extension office for demonstrations on PICS bags and metal silos. They can help farmers store produce safely.