Teff
Eragrostis tef
Poaceae
Ethiopian and Eritrean highlands; domesticated in Ethiopia, now also grown in Eritrea and on diaspora farms abroad
9.6800° N, 39.5300° E · Ethiopian highlands
15.3229° N, 38.9251° E · Asmara, Eritrea
A tufted annual grass, 40–120 cm tall, with loose open panicles that hang heavy with some of the smallest grains of any cereal — about 150 seeds weigh as much as one grain of wheat. The grain comes in white (nech), red-brown (key) and mixed (sergegna); white teff makes the pale, mild injera served to guests, red the darker, more strongly flavoured everyday kind. The whole grain is always milled whole — the seed is too small to polish — so teff flour is whole-grain flour by nature.
How it grows
Teff is a short-day C4 grass of the cool highlands, happiest at 1,800–2,100 m where days are warm and nights are cool. In Ethiopia it is sown at the start of the main kiremt rains in June–July on finely tilled, well-drained soil, and harvested 60–120 days later depending on variety and altitude. The seedbed must be fine as ash — the seed is dust-small and sown by hand-broadcasting, then trampled or brushed in rather than buried.
It tolerates waterlogging better than most cereals, which is why it survives the heavy highland rains, but it lodges easily: a storm near harvest lays the whole field flat, and a lodged field must be cut by hand. Yields are modest, roughly a tonne per hectare on smallholdings, which is part of why teff costs more than any other Ethiopian grain.
Grow at home
1. Teff needs a long warm season (over 90 frost-free days) and full sun; outside the highland tropics it is a curiosity crop, not a food crop.
2. Prepare the finest seedbed you can — raked, crumbled, stone-free — in a bed or a wide pot at least 20 cm deep.
3. Mix the tiny seed with dry sand (ten parts sand to one of seed) so it spreads evenly, broadcast thinly, and press in with a board. Do not cover.
4. Water with the finest mist you have; a hard jet washes the seed into puddles.
5. Thin to a few centimetres apart once the grass is finger-high. Harvest when the panicles turn straw-coloured and the seed is hard: cut, dry in a sheet, and rub out the grain.
Harvest
Cut when the straw turns golden and the grain is hard enough to crack under a tooth — in the highlands this is October–November. Because lodged fields are common, much of the harvest is cut with sickles, bound into sheaves, and dried in stooks for a week. Threshing is still done by oxen trampling the sheaves on a beaten threshing floor (awudema), then winnowing in the afternoon wind. The grain stores for years in a dry gotera (clay granary) — its tiny size leaves weevils little to work with.
Lore
White-teff injera is what a highland family serves when it wants to honour a guest; the everyday injera is red or mixed teff. The batter's starter, ersho, is kept from one batch to the next and passed on within families, so a household's injera keeps a taste of its own. During the long fasts of the Ethiopian Orthodox church, when animal foods are set aside for weeks, teff injera with shiro and misir carries the whole household.