Cold hardiness & minimum temperature

Is teff grass (Eragrostis tef)cold hardy? Hardiness zone & min temp

Also called teff grass, teff, Williams lovegrass, annual teff.

More about teff grass

About teff grass

Eragrostis tef · also called teff grass, teff · edible

Teff is a warm-season annual cereal grass originating in Ethiopia and Eritrea, where its tiny nutritious grains are the primary ingredient of injera flatbread. The smallest cereal grain in the world, teff is gluten-free, rich in calcium, magnesium, iron, and dietary fibre. Grown as an edible grain crop, hay, or cover crop and harvested within 45–90 days of sowing.

Cold limit: USDA Annual — grown in zones 4–11 as a summer crop · RHS H1c (tender annual; no frost tolerance at any growth stage) (15°C to 38°C (optimal 20–30°C for germination and growth; frost kills at any stage))

Watch for — Frost kill at any growth stage: Teff is completely frost-intolerant — a single frost event kills plants at any stage of growth. Do not sow until soil temperature consistently exceeds 18°C (65°F) and all risk of frost has passed. In northern climates, the growing window is typically late May to early September.

What teff grass's hardiness rating actually means

Hardiness works differently for teff grass: it is grown as a seasonal crop, not overwintered. The question is not "what zone" but "how long is your frost-free growing window". Its RHS rating of H1c means: Warm-temperate — can summer outdoors but must come in well before the first frost. On the US scale that maps to USDA Annual — grown in zones 4–11 as a summer crop — the zones where it can be left outdoors year-round.

New to these scales? The USDA hardiness zone map explained covers how the zone numbers work, and you can find your own zone with the zone finder.

Minimum temperature — and what happens below it

As an annual crop, its "minimum temperature" is the first hard frost — that is the end of the plant's life, not a survivable low. Many types are also damaged by light frost (around 0 °C).

Concretely, for teff grass as it gets too cold:

Light frost (around 0 to −2 °C) damages or kills tender summer crops outright; cold-hardy types take a few degrees of frost.
The plant does not "survive winter" — its life cycle simply ends, by design, when frost arrives or it finishes cropping.
A surprise late spring frost can also kill young transplants set out too early, before the season even starts.

Can teff grass go outside or overwinter — and where?

Time it to your frost dates: sow or plant out after the last spring frost, and aim to harvest before the first autumn frost.
In short-season zones, start it indoors or under cover to stretch the effective growing window.
Hardier crops in this group can be sown for an autumn or overwintered harvest in mild zones — check the specific crop.

Work back from your local frost dates with the frost-date calculator: the last spring frost and first autumn frost are what really decide when teff grass can be outside. US growers can check USDA zones; UK growers should use the RHS hardiness ratings, which match the H1c figure above.

Frost protection for borderline teff grass

teff grass is right on a hardiness edge in many gardens, so if you are pushing it, these measures buy it the margin it needs:

Use fleece, cloches or a cold frame at each end of the season to dodge a borderline frost and add growing weeks.
Have row cover ready for an unexpected late spring or early autumn frost.
Know your local last- and first-frost dates and count back the crop’s days-to-maturity to schedule the sowing.

teff grass hardiness — frequently asked questions

Is teff grass cold hardy?

Hardiness works differently for teff grass: it is grown as a seasonal crop, not overwintered. The question is not "what zone" but "how long is your frost-free growing window". A seasonal crop, not a perennial. teff grass is grown as an annual in USDA Annual — grown in zones 4–11 as a summer crop; you sow after the last frost and harvest before the first one, then start again next year.

What is the minimum temperature teff grass can survive?

As an annual crop, its "minimum temperature" is the first hard frost — that is the end of the plant's life, not a survivable low. Many types are also damaged by light frost (around 0 °C).

What hardiness zone is teff grass?

teff grass is rated USDA Annual — grown in zones 4–11 as a summer crop and RHS H1c — Warm-temperate — can summer outdoors but must come in well before the first frost.

Can teff grass survive winter outside?

Time it to your frost dates: sow or plant out after the last spring frost, and aim to harvest before the first autumn frost. In short-season zones, start it indoors or under cover to stretch the effective growing window. Hardier crops in this group can be sown for an autumn or overwintered harvest in mild zones — check the specific crop.

How do I protect teff grass from frost?

Use fleece, cloches or a cold frame at each end of the season to dodge a borderline frost and add growing weeks. Have row cover ready for an unexpected late spring or early autumn frost. Know your local last- and first-frost dates and count back the crop’s days-to-maturity to schedule the sowing.