Why Are Poinsettia Leaves Turning Yellow? Here Are All the Reasons

Poinsettia is a shrub plant in the Euphorbiaceae family, and it is cultivated in most parts of China. It is generally quite common in various gardens and parks, and it has high ornamental value. Its stems and leaves can also be used as medicine, with many medicinal effects. It is welcomed by many people, but when growing poinsettia, the phenomenon of yellowing leaves often occurs. So why do poinsettia leaves turn yellow? Let's take a look below!

1. Excessive light

Poinsettia has a certain demand for light. During the growth process of poinsettia, suitable light is very beneficial to its growth. But we also need to pay attention to controlling light intensity. If the light is too strong, especially if shading work is not done well during the strong light season in summer, then poinsettia leaves are very easily sunburned by sunlight, and because high temperature and dryness cause leaf moisture to evaporate too quickly, yellowing leaves and leaf drop occur. Therefore, when growing poinsettia, we should pay attention to maintaining a suitable light environment. In summer, shading work should be done well, and water should be sprayed appropriately to increase air humidity.

2. Temperature too low

Poinsettia likes to grow in a warm environment, and its cold tolerance is very poor. Its suitable growth temperature is about 18 degrees, and even at night in winter it needs a temperature above 15. If the temperature is below 5 degrees, then yellow leaves will occur because the temperature is too low. However, the temperature should not be too high either. If the temperature is too high, the moisture in poinsettia leaves will evaporate too quickly, and yellowing leaves and leaf drop are also likely. Therefore, we should control the temperature well, do a good job of heating and keeping warm in winter, and must not let poinsettia plants be exposed to direct cold wind. When the temperature is too high, cool it appropriately and spray reasonably to ensure normal growth of poinsettia.

3. Overwatering

Although poinsettia has a relatively large water requirement and likes to grow in a relatively humid environment, we still need to pay attention to controlling the amount of watering and must not water too much. If water accumulates in the soil, then it will inhibit root respiration, affect nutrient absorption, and root rot is also likely to occur. And many factors will therefore cause poinsettia leaves to turn yellow. So we should pay attention to controlling the amount of watering and not water too much. Adjust reasonably according to seasonal changes. For example, in spring, watering about once every three days to keep the soil moist is enough. In summer, water about once a day and spray appropriately around the plant.

4. Improper fertilisation

A variety has a relatively large demand for nutrients during its growth process, so when growing poinsettia we still need to do a good job of fertilising. In particular, we should pay attention to supplementing sufficient trace elements for poinsettia. If fertilisation is improper and the nutrient ratio in the fertiliser is unbalanced, then poinsettia leaves will also show leaf drop and yellowing as a result. Therefore, every year when we repot the plant, we should pay attention to applying an appropriate amount of base fertiliser. After each pruning, some dilute fertiliser water can be appropriately applied to provide sufficient nutrients for the growth of poinsettia.

The above is a brief introduction to why poinsettia leaves turn yellow. That is all for today's introduction. This article is for reference only, and we hope it can help everyone!