In biology, the BBCH-scale for leafy vegetables forming heads describes the phenological development of leafy vegetables forming heads, such as cabbage, chinese cabbage, lettuce and endive, using the BBCH-scale.
The phenological growth stages and BBCH-identification keys of leafy vegetables forming heads are:
Growth stageCodeDescription0: Germination00 Dry seed01 Beginning of seed imbibition03 Seed imbibition complete05 Radicle emerged from seed07 Hypocotyl with cotyledons breaking through seed coat09 Emergence: cotyledons break through soil surface1: Leaf development (Main shoot)10 Cotyledons completely unfolded; growing point or true leaf initial visible11 First true leaf unfolded12 2nd true leaf unfolded13 3rd true leaf unfolded1 . Stages continuous till ...19 9 or more true leaves unfolded4: Development of harvestable vegetative plant parts41 Heads begin to form: the two youngest leaves do not unfold42 20% of the expected head size reached43 30% of the expected head size reached44 40% of the expected head size reached45 50% of the expected head size reached46 60% of the expected head size reached47 70% of the expected head size reached48 80% of the expected head size reached49 Typical size, form and firmness of heads reached5: Inflorescence emergence51 Main shoot inside head begins to elongate53 30% of the expected height of the main shoot reached55 First individual flowers of main inflorescence visible (still closed)57 First individual flowers of secondary inflorescences visible (still closed)59 First flower petals visible; flowers still closed6: Flowering60 First flowers open (sporadically)61 Beginning of flowering: 10% of flowers open62 20% of flowers open63 30% of flowers open64 40% of flowers open65 Full flowering: 50% of flowers open67 Flowering finishing: majority of petals fallen or dry69 End of flowering7: Development of fruit71 First fruits formed72 20% of fruits have reached typical size73 30% of fruits have reached typical size74 40% of fruits have reached typical size75 50% of fruits have reached typical size76 60% of fruits have reached typical size77 70% of fruits have reached typical size78 80% of fruits have reached typical size79 Fruits have reached typical size8: Ripening of fruit and seed81 Beginning of ripening: 10% of fruits ripe, or 10% of seeds of typical colour, dry and hard82 20% of fruits ripe, or 20% of seeds of typical colour, dry and hard83 30% of fruits ripe, or 30% of seeds of typical colour, dry and hard84 40% of fruits ripe, or 40% of seeds of typical colour, dry and hard85 50% of the fruits ripe, or 50% of seeds of typical colour, dry and hard86 60% of fruits ripe, or 60% of seeds of typical colour, dry and hard87 70% of fruits ripe, or 70% of seeds of typical colour, dry and hard88 80% of fruits ripe, or 80% of seeds of typical colour, dry and hard89 Fully ripe: seeds on the whole plant of typical colour and hard9: Senescence92 Leaves and shoots beginning to discolour95 50% of leaves yellow or dead97 Plants dead99 Harvested product (seeds)
References
External links A downloadable version of the BBCH Scales