It takes an average of two to three years for the vine to produce its first flowers. Yellow-green flowers are ephemeral.
They appear in blades (racemes of 10 to 12 buds) pointing to the emergence of flowers.
Up to three to four blades can be found per vine. The flowering is staggered over about three months for a period between July and September, once each year.
Breeding
To obtain a vanilla bean, human intervention is necessary. Fertilization can be broken down into three phases:
*The lip of the flower is lowered and torn using a stylus or small stick to release the column and the gynostemium.
*The rostellum is lifted using the stylus and placed under the stamen.
*Using the finger, pressure is applied to bring the pollen mass into contact with the stigma.
On each blade, the flowers open one after the other. It is fairly rare to find two or three flowers open on the same blade. After the flower is fertilized, its base lengthens and moves downwards: this is the formation of the vanilla bean.
It will be two months before the dried flower falls. The bean has then reached its final size. But it is not until after the ninth month that the bean reaches full maturity.