BBCH-scale (potato)

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 stage	Code		Description
	2 digit	3 digit
0: Sprouting/Germination	00	000	Innate or enforced dormancy, Dry seed tuber not sprouted
	01	001	Beginning of sprouting: Beginning of sprouts visible (< 1 mm) seed imbibition
	02	002	Sprouts upright (< 2 mm)
	03	003	End of dormancy: sprouts 2–3 mm Seed imbibition complete
	05	005	Beginning of root formation Radicle (root) emerged from seed
	07	007	Beginning of stem formation Hypocotyl with cotyledons breaking
	08	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 surface
	09	009	Emergence: stems break through soil surface; cotyledons break through soil surface
		021–029^1
1: Leaf development	10	100	From tuber: first leaves begin to extend From seed: cotyledons completely unfolded
	11	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 rows
	32	302	20% of plants meet between rows
	33	303	30% of plants meet between rows
	34	304	40% of plants meet between rows
	35	305	50% of plants meet between rows
	36	306	60% of plants meet between rows
	37	307	70% of plants meet between rows
	38	308	80% of plants meet between rows
	39	309	Crop cover complete: about 90% of plants meet between rows
4: Tuber formation	40	400	Tuber initiation: swelling of first stolon tips to twice the diameter of subtending stolon
	41	401	10% of total final tuber mass reached
	42	402	20% of total final tuber mass reached
	43	403	30% of total final tuber mass reached
	44	404	40% of total final tuber mass reached
	45	405	50% of total final tuber mass reached
	46	406	60% of total final tuber mass reached
	47	407	70% of total final tuber mass reached
	48	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 stage
5: Inflorescence (cyme) emergence	51	501	First individual buds (1–2 mm) of first inflorescence visible (main stem)
	55	505	Buds of first inflorescence extended to 5 mm
	59	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 sepals
	5N .		Nth inflorescence emerging
6: Flowering	60	600	First open flowers in population
	61	601	Beginning of flowering: 10% of flowers in the first inflorescence open (main stem)
	62	602	20% of flowers in the first inflorescence open
	63	603	30% of flowers in the first inflorescence open
	64	604	40% of flowers in the first inflorescence open
	65	605	Full flowering: 50% of flowers in the first inflorescence open
	66	606	60% of flowers in the first inflorescence open
	67	607	70% of flowers in the first inflorescence open
	68	608	80% of flowers in the first inflorescence open
	69	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 inflorescence
	6N .		Nth inflorescence flowering
		6N9	End of flowering
7: Development of fruit	70	700	First berries visible
	71	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 size
	73	703	30% of berries in the first fructification have reached full size
	7 .	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 seed	81	801	Berries in the first fructification still green, seed light-coloured (main stem)
	85	805	Berries in the first fructification ochre-coloured or brownish
	89	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 fructification
9: Senescence	91	901	Beginning of leaf yellowing
	93	903	Most of the leaves yellowish
	95	905	50% of the leaves brownish
	97	907	Leaves and stem dead, stems bleached and dry
	99	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 phonological 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