The BBCH-scale (potato) identifies the phenological development stages of a potato (Solanum tuberosum). It is a plant species-specific version of the BBCH-scale.

Growth stageCodeDescription2 digit3 digit0: Sprouting/Germination00 000 Innate or enforced dormancy, Dry seed tuber not sprouted01 001 Beginning of sprouting: Beginning of sprouts visible (< 1 mm) seed imbibition02 002 Sprouts upright (< 2 mm)03 003 End of dormancy: sprouts 2–3 mm Seed imbibition complete05 005 Beginning of root formation Radicle (root) emerged from seed07 007 Beginning of stem formation Hypocotyl with cotyledons breaking08 008 Stems growing towards soil surface, Hypocotyl with formation of scale leaves in the axils; cotyledons growing of which stolons will develop later towards soil surface09 009 Emergence: stems break through soil surface; cotyledons break through soil surface021–02911: Leaf development10 100 From tuber: first leaves begin to extend From seed: cotyledons completely unfolded11 101 First leaf of main stem unfolded (> 4 cm)12 102 Second leaf of main stem unfolded (> 4 cm)13 103 Third leaf of main stem unfolded (> 4 cm)1 . 10 . Stages continuous till ...19 109 Nine or more leaves of main stem unfolded (> 4 cm) (2 digit);2 9 leaves of main stem unfolded (> 4 cm) (3 digit) 110 Tenth leaf of main stem unfolded (> 4 cm)11 . Stages continuous till ... 119 Nineteenth leaf of main stem unfolded (> 4 cm) 121 First leaf of second order branch above first inflorescence unfolded (> 4 cm) 122 Second leaf of second order branch above first inflorescence unfolded (> 4 cm)12 . Stages continuous till ... 131 First leaf of third order branch above second inflorescence unfolded (> 4 cm) 132 Second leaf of third order branch above second inflorescence unfolded (> 4 cm)13 . Stages continuous till ... 1NX Xth leaf of nth order branch above (n-1)th inflorescence unfolded (> 4 cm)2: Formation of basal side shoots below and above soil surface (main stem)21 201 First basal side shoot visible (> 5 cm)22 202 Second basal side shoot visible (> 5 cm)23 203 Third basal side shoot visible (> 5 cm)2 . 20 . Stages continuous till ...29 209 Nine or more basal side shoots visible (> 5 cm)3: Main stem elongation (crop cover)31 301 Beginning of crop cover: 10% of plants meet between rows32 302 20% of plants meet between rows33 303 30% of plants meet between rows34 304 40% of plants meet between rows35 305 50% of plants meet between rows36 306 60% of plants meet between rows37 307 70% of plants meet between rows38 308 80% of plants meet between rows39 309 Crop cover complete: about 90% of plants meet between rows4: Tuber formation40 400 Tuber initiation: swelling of first stolon tips to twice the diameter of subtending stolon41 401 10% of total final tuber mass reached42 402 20% of total final tuber mass reached43 403 30% of total final tuber mass reached44 404 40% of total final tuber mass reached45 405 50% of total final tuber mass reached46 406 60% of total final tuber mass reached47 407 70% of total final tuber mass reached48 408 Maximum of total tuber mass reached, tubers detach easily from stolons, skin set not yet complete (skin easily removable with thumb)49 409 Skin set complete: (skin at apical end of tuber not removable with thumb) 95% of tubers in this stage5: Inflorescence (cyme) emergence51 501 First individual buds (1–2 mm) of first inflorescence visible (main stem)55 505 Buds of first inflorescence extended to 5 mm59 509 First flower petals of first inflorescence visible 521 Individual buds of second inflorescence visible (second order branch) 525 Buds of second inflorescence extended to 5 mm open (main stem) 529 First flower petals of second inflorescence visible above sepals 531 Individual buds of third inflorescence visible (third order branch) 535 Buds of third inflorescence extended to 5 mm 539 First flower petals of third inflorescence visible above sepals5N . Nth inflorescence emerging6: Flowering60 600 First open flowers in population61 601 Beginning of flowering: 10% of flowers in the first inflorescence open (main stem)62 602 20% of flowers in the first inflorescence open63 603 30% of flowers in the first inflorescence open64 604 40% of flowers in the first inflorescence open65 605 Full flowering: 50% of flowers in the first inflorescence open66 606 60% of flowers in the first inflorescence open67 607 70% of flowers in the first inflorescence open68 608 80% of flowers in the first inflorescence open69 609 End of flowering in the first inflorescence 621 Beginning of flowering: 10% of flowers in the second inflorescence open (second order branch) 625 Full flowering: 50% of flowers in the second inflorescence open 629 End of flowering in the 2nd inflorescence 631 Beginning of flowering: 10% of flowers in the third inflorescence open (third order branch) 635 Full flowering: 50% of flowers in the third inflorescence open 639 End of flowering in the third inflorescence6N . Nth inflorescence flowering 6N9 End of flowering7: Development of fruit70 700 First berries visible71 701 10% of berries in the first fructification have reached full size (main stem)72 702 20% of berries in the first fructification have reached full size73 703 30% of berries in the first fructification have reached full size7 . 70 . Stages continuous till ... 721 10% of berries in the second fructification have reached full size (second order branch)7N . Development of berries in nth fructification 7N9 Nearly all berries in the nth fructification have reached full size (or have been shed)8: Ripening of fruit and seed81 801 Berries in the first fructification still green, seed light-coloured (main stem)85 805 Berries in the first fructification ochre-coloured or brownish89 809 Berries in the first fructification shrivelled, seed dark 821 Berries in the second fructification still green, seed light-coloured (second order branch)8N . Ripening of fruit and seed in nth fructification9: Senescence91 901 Beginning of leaf yellowing93 903 Most of the leaves yellowish95 905 50% of the leaves brownish97 907 Leaves and stem dead, stems bleached and dry99 909 Harvested product

1 For second generation sprouts 2 Stem development stops after termination of main stem by an inflorescence. Branches arise from axils of upper leaves of the main stem, exhibiting a sympodial branching pattern References

H. Hack, H. Gall, Th. Klemke, R. Klose, U. Meier, R. Stauss, A. Witzenberger. 2001. The BBCH scale for phenological growth stages of potato (Solanum tuberosum L.). U. Meier (Ed.), Growth Stages of Mono and Dicotyledonous Plants, BBCH Monograph, Federal Biological Research Centre for Agriculture and Forestry.

External links A downloadable version of the BBCH Scales Alternative link to pdf above