EWS-Agronomy Troubleshooting Guide
Flower Drop
There are multiple environmental factors responsible for flower drop, these are:
Lack or irregularity in nutrition
Temperature fluctuation
Excessive Wind
Lack of Moisture Humidity
In the gourd family, male flowers naturally drop off after few days once their main purpose of pollinating the female flowers is complete. Many factors influence the reproductive success of plants.
Understanding the biotic and abiotic processes involved will help you develop realistic expectations and take the appropriate steps to facilitate the processes involved.
Environmental Factors Causing Flower Drop Flower Drop (2)
Lack or Irregularity in Nutrition 1
This creates stress in plants. Higher or lower concentration of nitrogen fertilizer will lead to blossom drop.
A higher dose encourages the vegetative growth in the plant while a lower dose cannot support further reproductive growth in the plant.
Temperature fluctuation 2
At higher temperatures, pollen becomes dry while at lower temperatures pollen becomes nonviable. Both of these lead to no pollination in the flower.
In the case of solanaceous such as tomatoes, chilly, brinjal, etc., the day temperature that is more than 35˚ C can cause flower drop. Night temperature that is more than 24˚ C or less than 10˚ C could also lead to flower drop.
3
Excessive Wind
It may carry away pollens or desiccate the flowers. It could also physically damage the plants by breaking the flowering branches.
Lack of Moisture 4
Lack of moisture or sudden and excess watering at once create a stress condition in the plant leads to flower drop.
Humidity 5
This plays a major role in pollen shedding.
Flower Drop (3)
Environmental Factors Causing Flower Drop
High & Low Relative Humidity (RH)
High RH interferes in improper pollen shedding and low RH makes pollen dry and it will not adhere to the stigma of the flower.
Light 7
Lack or excessive sunlight exposure results in the poor setting of fruits.
Heavy Fruit Set
In order to maintain a balance in the plant system, the plant itself abort some flowers when it blooms in.
Insect Damage and Disease
7
Small insects like thrips and flies - lead to less nutrition supply to the developing buds/ flowers. This could lead to bud/ flower drop.
Improper Pollination or Lack of Pollination
When flowers do not get proper pollination within a particular time period this causes the flower to fall off. Without pollination, the little fruit will soon wither and drop off the vine.
Flower Drop (4)
What Measures to Follow or to Monitor?
Use season adaptable varieties for the geography. Grow varieties that are suitable to the region and climate. Choose varieties that can tolerate high or low temperature.
Crop Nutrition: Ensure provision of proper macro and micro nutrition to the plants. Micronutrients such as Boron are important for flower development.
1. Crop Irrigation: Regularly water the plants in the right quantity depending on the climatic conditions. The growth medium should always be kept moist.
2. Monitor for pest activity at regular intervals.
3. Check for excessive flowering or fruit set. Prune out extra flower clusters.