Feed & nutrition3 min read
How to make maize silage on a small farm (bag and pit methods)
Silage stores green fodder for months without losing much quality. Step-by-step: when to harvest, how to chop, pack and seal, and how to tell good silage from bad.
Green grass is plentiful in the rainy season and scarce in the dry months, so milk drops when the grass runs out. Silage solves this. It is green fodder that is chopped, packed tightly and sealed without air, so natural bacteria turn its sugars into acid that keeps it, like a pickle, for many months.
Which crop?
- Maize is the easiest and best silage crop: plenty of sugar for good fermentation and high energy for milk.
- Sorghum also works well.
- Napier and other grasses can be ensiled too, but they have less sugar. Mixing in molasses (about 3% of the green weight, diluted with a little water) helps them ferment properly.
Harvest at the right time
Cut maize when the grains are at the milk-to-dough stage (a grain pressed with a fingernail gives a thick, milky paste), roughly 75–90 days after sowing depending on the variety. At this stage the whole plant has about the right dryness: around 30–35% dry matter.
The squeeze test: take a handful of chopped material and squeeze hard for 30 seconds.
- Water drips out: too wet; wilt it in the sun for a few hours.
- Holds a ball and the hand is moist: just right.
- Falls apart immediately and feels dry: too dry; it will be hard to pack.
Two methods for small farms
Bag silage
Thick plastic silage bags hold about 50–100 kg each. Easy to handle, little waste once opened, and you can move them.
Pit or bunker silage
A pit dug in high ground or a cement bunker, lined with thick plastic. Better for larger amounts. Choose a place where rainwater cannot flow in.
Step by step
- Chop into 1–2 cm pieces with a chaff cutter. Short pieces pack tightly.
- Fill quickly: finish a bag or a pit section on the same day if possible.
- Pack hard, layer by layer. In a bag, press and tamp every few centimetres; in a pit, trample each 15–20 cm layer well. Pushing out air is the most important step.
- Seal airtight. Squeeze the remaining air out of a bag and tie it tightly. Cover a pit with thick plastic and weigh it down all over with soil, sand bags or old tyres.
- Protect from rats, birds and sharp objects. Check for holes every week and tape them at once.
- Wait at least 3 weeks; most farmers open after 30–45 days.
Good or bad silage?
| Good silage | Bad silage |
|---|---|
| Yellow-green to light brown | Dark brown or black |
| Pleasant, sour, fruity smell (like pickle) | Rotten, ammonia or strong vinegar smell |
| Firm, not slimy | Slimy, or with white, blue or black mould |
Never feed mouldy or rotten silage. It can make cows sick or cause abortion. Throw away the spoiled part.
Feeding silage
- Start with a small amount and build up over 1–2 weeks.
- An adult milking cow can eat about 10–15 kg a day alongside straw, grass and concentrate.
- Once opened, keep the face or bag covered and use it within a few days; air spoils it quickly.
- Take out only what you feed that day.
Is it worth it?
Count your costs (crop, chopping, bags or plastic, labour) and compare them with buying fodder or extra concentrate in the dry season. Record them in FarmFlows → Finance and watch your milk record through the dry months; steady milk from February to April is the payoff.
Quick checklist
- Maize at milk-to-dough stage, about 30–35% dry matter
- Chop 1–2 cm, fill fast, pack hard, seal airtight
- Wait 30–45 days
- Sour, fruity smell = good; mould or rot = throw away
- Build up to 10–15 kg a day per milking cow