The growth stages of cereals

It is useful to break down the cereal life cycle into various growth stages. By understanding the main crop development stages, it becomes easier to measure crop performance and informs husbandry choices.

The BBCH (Biologische Bundesanstalt, Bundessortenamt und CHemical Industry) scale is the main system in cereals, based on ten developmental phases – the principal growth stages (GS). Understanding the system can aid with the benchmarking of crop development and help assist management decisions. For example, this uniform coding system features on plant protection product labels.

GS00: Dry seed – caryopsis

GS01: Beginning of seed imbibition

GS03: Seed imbibition complete

GS05: Radicle emerged

GS06: Radicle elongated, root hairs and/or side roots visible

GS07: Coleoptile – pointed protective sheath covering the emerging shoot – emerged

GS09: Emergence. Coleoptile penetrates soil surface – cracking stage

GS10: First leaf through coleoptile

GS11: First leaf unfolded, ligule visible

GS13: Three leaves unfolded on the main shoot

GS15: Five leaves unfolded

GS19: Nine or more leaves unfolded on the main stem

GS20: Main shoot only, no tillers

GS21: Main shoot and one tiller

GS23: Main shoot and three tillers

GS25: Main shoot and five tillers

GS29: Main shoot and nine or more tillers

GS30: Ear at 1cm, pseudostem erect

GS31: First node detectable

GS32: Second node detectable

GS33: Third node detectable

GS37: Flag leaf just visible

GS39: Flag leaf fully unrolled, ligule just visible

An internode is the part of a plant stem between two successive nodes. The first node detectable must be above an internode of at least 1cm*. The second and subsequent nodes detectable must be above an internode of at least 2cm. *Sometimes a node may be underground and bear roots. As long as the internode below it exceeds 1cm, count it.

GS41: Flag leaf sheath extending – early-boot stage

GS43: Flag leaf sheath just visibly swollen – mid-boot stage

GS45: Flag leaf sheath swollen – late-boot stage

GS47: Flag leaf sheath opening

GS49: First awns visible

GS51: First spikelet of ear just visible above flag leaf ligule

GS55: Half of ear emerged above flag leaf ligule

GS59: Ear completely emerged above flag leaf ligule

GS61: Start of flowering – first anthers visible

GS65: Flowering halfway – 50% of anthers mature

GS69: Flowering complete – some dehydrated anthers may remain

GS71: Watery ripe – first grains half final size

GS73: Early milk

GS75: Medium milk – grain content milky, grains reached final size

GS77: Late milk

GS83: Early dough

GS85: Soft dough – content soft but dry

GS87: Hard dough – thumbnail impression held

GS89: Fully ripe – grain hard, difficult to divide with thumbnail

GS91: Grain hard – difficult to divide

GS92: Grain hard – not dented by thumbnail

GS93: Grain loosening in daytime

GS97: Plant dead and collapsing

GS99: Harvested product