What to Do When Potted Flower Leaves Turn Yellow? Causes and Solutions
1) Soil is too acidic. If you grow flowers in the southern provinces, since the soil there is mostly acidic, planting alkaline-loving plants such as oleander, boxwood, elm-leaved spirea, sweet pea, and winter jasmine (they thrive in soil with a pH of 7-8) may also cause adverse reactions to excessive acidity, resulting in poor branching and weak, yellowing leaves and branches.
When this happens, you should repot and replace the soil, and you can mix an appropriate amount of plant ash into the soil. If testing shows the pH is below the proper value, you can mix a small amount of lime into the soil, which can significantly reduce soil acidity.
2) Poor air permeability and light transmission. For flowers to grow and develop well, conditions such as sunlight, water, temperature, soil, and fertilizer all need to be suitable. If air permeability is poor and sunlight is insufficient, it is also difficult for flowers to grow vigorously.
Some inexperienced flower growers apply too much nitrogen fertilizer, causing branches and leaves to grow too luxuriantly. Combined with failure to prune in time, the branches and leaves grow so densely that air cannot pass through, and sunlight cannot reach the whole plant, affecting the plant's respiration and photosynthesis, causing nutritional imbalance and the decline phenomenon of yellowing and falling leaves.
When this situation is discovered, prune in time, remove excess branches and leaves such as those in the same position or overlapping, and pay attention to reasonably applying some phosphorus and potassium fertilizer so that the flowers receive balanced and comprehensive nutrition.
3) The air is too dry. After entering winter, most flowers are moved indoors. In order to increase the temperature, people often burn stoves indoors to keep warm. Because the stove burns all day, the moisture in the indoor air quickly decreases, and it may even become very dry.
This environment is very unfavorable for flowers, especially for some moisture-loving flowers such as hibiscus, jasmine, white orchid, banana shrub, and monstera, which are prone to phenomena such as scorched leaf tips or leaf margins, scorched spots on leaves, and curled leaves.
At this time, you should spray the leaf surfaces and branches with slightly warm clean water; for some precious flowers such as zhulan, orchids, clivia, camellia, and peony, after spraying with clean water, cover them with a cover made from a plastic bag (cut off two corners of the plastic bag as ventilation holes). Each time you spray water, remove the cover to spray, and put it back on after spraying.