Winter rye

Secale cereale

The hardiest winter cereal — grows when nothing else will. Standard autumn-sown cover crop in cold-climate gardens; exceptional root system improves soil structure.

Hardiness ratings

Winter rye hardiness across the four zone systems
SystemRatingTemperature rangeHow to read it
USDA hardiness zone Zone 3–9 −40 °C to −1.1 °C Zones where it can be grown as an annual — not a frost-tolerance rating
RHS hardiness rating H7 down to −20 °C Plant needs at least this level of cold tolerance
Canadian plant hardiness zone Zone 3–9 −34 °C and warmer Zones where it can be grown as an annual — not a frost-tolerance rating
Australian (ANBG) zone Zone 1–5 −15 °C to 10 °C Zones where it can be grown as an annual — not a frost-tolerance rating

As a tender annual, Winter rye doesn't overwinter — the zone range shows where the growing season supports it. See the RHS rating for its actual cold tolerance.

Growing notes

  • More cold-hardy than winter wheat or barley — establishes through autumn and grows through winter mild spells
  • Allelopathic — releases compounds that suppress germination of weed seeds and small-seeded crops; avoid as a precursor to direct-seeded carrots, lettuces, or alliums
  • Terminate well before seed set or it becomes a weed itself

Categories

Related plants

Cross-check Winter rye against your zones

Reference

Winter rye on Wikipedia