# BBCH-scale (sunflower)

The BBCH-scale (sunflower) identifies the phenological development stages of the sunflower (Helianthus annuus). It is a plant species specific version of the BBCH-scale.
Phenological growth stages and BBCH-identification keys of sunflower :
| Code | Description |
| Principal growth stage 0: Germination ||
| 00 | Dry seed (achene) |
| 01 | Beginning of seed imbibition |
| 03 | Seed imbibition complete |
| 05 | Radicle emerged from seed |
| 06 | Radicle elongated, root hairs developing |
| 07 | Hypocotyl with cotyledons emerged from seed |
| 08 | Hypocotyl with cotyledons growing towards soil surface |
| 09 | Emergence: cotyledons emerge through soil surface |
| Principal growth stage 1: Leaf development$^1$ ||
| 10 | Cotyledons completely unfolded |
| 12 | 2 leaves (first pair) unfolded |
| 14 | 4 leaves (second pair) unfolded |
| 15 | 5 leaves unfolded |
| 16 | 6 leaves unfolded |
| 17 | 7 leaves unfolded |
| 18 | 8 leaves unfolded |
| 19 | 9 or more leaves unfolded |
| Principal growth stage 3: Stem elongation ||
| 30 | Beginning of stem elongation |
| 31 | 1 visibly extended internode |
| 32 | 2 visibly extended internodes |
| 33 | 3 visibly extended internodes |
| 3 . | Stages continuous till ... |
| 39 | 9 or more visibly extended internodes |
| Principal growth stage 5: Inflorescence emergence ||
| 51 | Inflorescence just visible between youngest leaves |
| 53 | Inflorescence separating from youngest leaves, bracts distinguishable from foliage leaves |
| 55 | Inflorescence separated from youngest foliage leaf |
| 57 | Inflorescence clearly separated from foliage leaves |
| 59 | Ray florets visible between the bracts; inflorescence still closed |
| Principal growth stage 6: Flowering ||
| 61 | Beginning of flowering: ray florets extended, disc florets visible in outer third of inflorescence |
| 63 | Disc florets in outer third of inflorescence in bloom (stamens and stigmata visible) |
| 65 | Full flowering: disc florets in middle third of inflorescence in bloom (stames and stigmata visible) |
| 67 | Flowering declining: disc florets in inner third of inflorescence in bloom (stames and stigmata visible) |
| 69 | End of flowering: most disc florets have finished flowering, ray florets dry or fallen |
| Principal growth stage 7: Development of fruit ||
| 71 | Seeds on outer edge of the inflorescence are grey and have reached final size |
| 73 | Seeds on outer third of the inflorescence are grey and have reached final size |
| 75 | Seeds on middle third of the inflorescence are grey and have reached final size |
| 79 | Seeds on inner third of the inflorescence are grey and have reached final size |
| Principal growth stage 8: Ripening ||
| 80 | Beginning of ripening: seeds on outer third of anthocarp black and hard. Back of anthocarp still green |
| 81 | Seeds on outer third of anthocarp dark and hard. Back of anthocarp still green |
| 83 | Dark of anthocarp yellowish-green, bracts still green. Seeds about 50% dry matter |
| 85 | Seeds on middle third of anthocarp dark and hard. Back of anthocarp yellow, bracts brown edged. Seeds about 60% dry matter |
| 87 | Physiological ripeness: back of the anthocarp yellow. Bracts marbled brown. Seeds about 75–80% dry matter |
| 89 | Fully ripe: seeds on inner third of anthocarp dark and hard. Back of anthocarp brown. Bracts brown. Seeds about 85% dry matter |
| Principal growth stage 9: ||
| 92 | Over ripe, seeds over 90% dry matter |
| 97 | Plant dead and dry |
| 99 | Harvested product |
1 Stem elongation may occur earlier than stage 19; in this case continue with the principal stage 3