Chilli Flower Drop Off and Chilli Plant VPD
A variety of factors influence whether a chilli flower stays on the branch or drops off. Even with ideal climate, soil, and growing conditions, some flower drop-off is natural since chilli plants produce more flowers than they need.
Early Flower Stage
When a chilli plant begins flowering, the buds initially remain closed. As they open, revealing the pistils, there may not be any pollen initially. Over the following week, the flower petals should fully open, and pollen should appear.
If flowers open without pollen, then turn yellow, die, and drop off, it’s an indication that something is wrong with the plant.
Stress and VPD (Vapour Pressure Deficit)
The primary factor causing flower drop-off is stress due to an unsuitable VPD (Vapour Pressure Deficit) rating.
For instance:
A hot, sunny window with low humidity creates dry air and a high VPD rate, preventing fertile flower and pollen production.
Conversely, cold, humid conditions result in a low VPD rate, causing the same issue.
You can find more details on VPD in our VPD Guide.
Remedies for Flower Drop-Off
Some chilli plants tolerate higher VPD rates better, such as non-super hot, wild, or rare varieties, making them more suitable for indoor growing. If flower drop-off persists, consider the following tips:
- Increase Humidity: Use a fogger in a saucer of water to create a gentle mist around the plant.
- Improve Ventilation: Open a window to allow fresh air to circulate, as natural air and heat are more balanced than stagnant conditions near a hot window.
- Move the Plant: Relocate the plant away from direct sunlight and overly warm areas.
- Use a Fan: Set up a fan to create a gentle breeze around the plant, avoiding strong wind.
- Mist the Plant: Lightly spray the plant with water to raise humidity levels.
The ultimate goal is to achieve a VPD score of 1.0–1.2 for optimal chilli plant health.
Overfeeding and Energy Mismanagement
If your chilli plant is healthy, with bushy foliage, fertile flowers, and developing pods, but still experiences excessive flower drop-off, overfeeding may be the issue.
When a plant receives too much feed, it may produce more flowers than it can support, shedding the excess due to lack of energy. Adjust feeding levels to help the plant focus on maintaining its flowers and pods.
Underfeeding and Energy Mismanagement
Similarly, if you have too much energy and not enough feed or irregular feed the plant will think it has enough to grow x amount of flowers and pods, but when it gets there it doesn't have enough feed it will drop off the flowers
Consistency is Key
Throughout the growing guide I mention consistency is key, it really is, the more consistent your growing climate is, the better the results will be with your chilli plant