Factors Affecting the Yield of Industrial Hemp – Experimental Results from France - Hemp: Industrial Production and Uses - page 74

Table 5.1. The different stages of development of Cannabis sativa L. according to the Médiavilla method.

Code Definition Remarks

Germination and emergence
0000 Dry seed

0001 Appearance of radicle

0002 Appearance of hypocotyl

0003 Opening of cotyledons

Vegetative stages
1002 First set of leaves 1 node

1004 Second set of leaves 3 nodes

1005 Third set of leaves 5 nodes

10xx nth set of leaves

Flowering and seed formation
2000 Changing point Change of phyllotaxis on the stem

2001 Flower buds

Dioecious plants
Male
2100 Flower formation First closed staminate flowers

2101 Beginning of flowering First opened staminate flowers

2102 Flowering 50% opened staminate flowers

2103 End of flowering 95% of staminate flowers open or withered

Female
2200 Flower formation First pistillate flowers; bract with no styles

2201 Beginning of flowering Styles of first female flowers

2202 Flowering 50% of bracts formed

2203 Beginning of seed maturity First seeds hard

2204 Seed maturity 50% of seeds hard

2205 End of seed maturity 95% of seeds hard or shattered

Monoecious plants
2300 Female flower formation First pistillate flowers; perigonal bract with

no pistils

2301 Beginning of female flowering First pistils visible

2302 Female flowering 50% of bracts formed

2303 Male flower formation First closed staminate flowers

2304 Male flowering Most staminate flowers open

2305 Beginning of seed maturity First seeds hard

2306 Seed maturity 50% of seeds hard

2307 End of seed maturity 95% of seeds hard or shattered

Senescence
3001 Leaf desiccation Leaves dry

3002 Stem desiccation Leaves dropped

3003 Stem decomposition Bast fibres free

Source : From Médiavilla et al . (1998) in International Hemp Association 5(2), 65-72.

Leaf dry weight

maturity. The curves for different varieties are
offset in time but parallel; this is explained by
differences in maturity.
Nitrogen fertilization is critical for seed
yield: in the same way as for hurds, the more
nitrogen, the higher the seed yield.

Regardless of the variety, the leaf dry weight devel-
ops vigorously at the start of the growth cycle and
attains 1.5 t/ha on average by 1 July. This increase
continues during the flowering period and reaches
an average of 2.5 t/ha by the end of August. Leaf