It's time to bloom

Coffee flowering is directly related to the productivity of the coffee plant. Under natural conditions, flowering is induced by the first rains after a dry period. It usually occurs from September to November, when the differentiated flower buds, after going through a dormant period, become sensitive or physiologically mature and react to external stimuli that trigger rapid growth, which lasts about 10 days, depending on the temperature, leading to the opening of the flowers (anthesis), completing the flowering process.

Several factors such as diseases, photoperiod, temperature, water availability and hormonal balance interfere with flowering. Being aware of these factors that interfere with flowering is essential to achieve high productivity. Leaf area, photosynthetic activity of the leaves and an adequate supply of carbohydrates are essential for flowering to take place.

The abortion of some of the coffee plant flowers is a process that will occur, as coffee plants produce many more flowers than those that actually develop into fruits, that is, the coffee plant produces more flowers than the photoassimilate reserves are capable of transforming into fruits. However, leaf retention and adequate nutrition mitigate floral abortion.

Do you know how much a coffee flower represents in bags per hectare? Based on the production components of the coffee crop, we can calculate the economic impact of the loss of a coffee flower. Table 1 presents average data on the components of coffee production to illustrate the impact of the loss of a flower on crop productivity.

Based on the values ​​in Table 1, we can calculate the loss of one flower per rosette. And it is possible to conclude that a single flower lost per rosette can result in an average loss of 8 bags of Arabica coffee per hectare, demonstrating, in a practical way, the importance of flowers for the productivity of the coffee plant.

Flowers/plant = 1 x 5 x 80 = 400

Flowers/plant = 1 x 5 x 80 = 400

Fruits/ha = 400 x 5.000 = 2.000.000

Liters/ha = 2.000.000 / 500 (fruits/liter) = 4.000

Bags/ha = 4.000 x 500 (liters/bag) = 8 bags/ha

Innovative practices in the management of coffee plant nutrition and physiology are important to allow plants to reach their maximum production potential. Mineral nutrition is a fundamental factor for the development of coffee plants and consequently good development and payment of flowering. Fertilization with macro and micronutrients in a balanced and personalized manner for each plot of the crop ensures that coffee plants have the necessary elements to guarantee the greatest flowering set and consequently the greatest production of coffee fruits.

In addition to mineral nutrition, knowledge of the physiology of the coffee plant and crop management through the application of biostimulants, technologies that act on the plant's metabolism, have shown positive effects on greater flowering set, especially by acting to mitigate abiotic stress in coffee plants.

The main categories of plant biostimulants are: (i) microorganisms, including beneficial bacteria and fungi; (ii) humic acids; (iii) fulvic acids; (iv) amino acids; and (v) seaweed extracts. When applied to crops, biostimulants stimulate plant metabolism, increasing the efficiency of nutrient absorption, tolerance to abiotic stresses and, consequently, increasing productivity and improving the quality of the harvested product.

It is also increasingly evident that interactions between microorganisms and plants influence crop responses to stresses such as heat, water deficit, flooding, salinity and heavy metals. Bioinputs are innovative technologies used in coffee plant management to promote greater flowering. Microorganisms can act through mechanisms such as mineralization and nutrient availability, hormone secretion, production of siderophores and other secondary metabolites, biofilm formation, cell signaling and disease suppression.

The management strategies mentioned above can be adopted and, when used well and adapted to the management of each farm, contribute to the success of the flowering. In addition, they play an important role in the development of a more integrative and sustainable coffee farming.

* By Karla Vilaca Martins, agricultural engineer, technical development consultant at ICL