Why are the leaves of the Hawaiian bamboo turning yellow, and what should be done?

1. Improper fertilizer

When cultivating it, we all choose some leaf mold soil, river sand soil, etc., and then mix them with a small amount of organic fertilizer to make a growing medium. This way it will survive more easily in the early stage. Then, from March to October every year, apply liquid fertilizer to it once every 2 weeks, which will make the leaf color deeper and greener. If the above is not done, its nutrients will not be supplied, and yellow leaves are unavoidable. So fertilizing must also be done appropriately.

2. Improper humidity

During its growing period, the soil must always be kept moist, and the air must not be too dry either, otherwise the humidity will drop, and the leaves will become dull and even withered and yellow. When the air is dry, we can often spray water on its leaves to raise the air humidity, which will keep its leaf color deep green. It can be seen that humidity is also a reason affecting leaf color.

3. Improper light

It is very afraid of strong light. If it is accidentally exposed to strong light, the leaves will turn yellow. It generally prefers a semi-shaded environment, and it is very tolerant of shade for a long time; even staying in a dark place for 1 to 2 months is no problem. So when caring for it normally, if you really give it sun exposure, it can only accept some bright scattered light.

4. Improper watering

Although it likes a moist environment, the water must not be too plentiful either, otherwise the potting soil will become too wet, causing root rot, affecting the plant's nutrient transport, and then making the leaves yellow. So watering must be moderate to keep the leaf color deep green.

5. Caused by disease

When the temperature is extremely high and the humidity is extremely high, it is prone to some diseases. These diseases will directly affect its plant, making it unable to grow normally, and then also causing nutrient deficiency, leading to yellow leaves. So we need to discover and prevent and treat them in time to prevent the leaves from being damaged.

Differences between Hawaiian bamboo and Phoenix tail bamboo

Difference in appearance

Hawaiian bamboo

Belongs to the palm family (Arecaceae), plant height 1~3 m. The stem nodes are hollow, relatively slender, with obvious nodes. New shoots grow from the stem, with no branching.

Its leaves grow on the upper part of the rhizome and are relatively sparse, with no leaves on the lower part of the rhizome. The leaves are relatively slender, dark green in color, and pinnate. There are relatively few leaflets on a single branch, and the leaf spacing is relatively large. The flowers are spadix inflorescences, generally pink, growing on the upper part of the stem.

Phoenix tail bamboo

Belongs to the tree family, plant height 3~6 m. The stem nodes are hollow, relatively long and thin, with many branches.

Its leaves grow on the upper part of the rhizome and are relatively dense, with few leaves on the lower part of the rhizome. The leaves are relatively narrow and long, linear, some even needle-shaped, and the leaf color is green. There are many leaflets on a single branch, and the leaf spacing is relatively small. The flowers are spadix inflorescences, generally tender yellow.

(Hawaiian bamboo)

Difference in growth habits

Hawaiian bamboo

Likes a high-temperature and high-humidity growing environment, has strong shade tolerance, and fears direct sunlight.

Suitable for surviving at a temperature of 20°C~30°C. It has strong cold resistance and can overwinter at temperatures above 2°C.

It has a relatively large demand for water. In addition to normal watering, it also needs water sprinkled around the plant to ensure a moist environment.

It has relatively high soil adaptability and can adapt to different soils.

Phoenix tail bamboo

Likes light, is slightly shade-tolerant, cannot go without light for a long time, but cannot accept sun exposure.

Suitable for surviving at temperatures above 10°C, with poor cold resistance, and cannot be frozen.

It likes moisture but fears waterlogging; long-term waterlogging will cause root rot in the plant.

It likes acidic and slightly acidic environments, and is not easy to grow in alkaline soil.

(Hawaiian bamboo)

Difference in distribution range

Hawaiian bamboo

Native to Mexico, it mainly grows in the tropical regions of South America. Now Taiwan, China is also planting it in batches, becoming one of its main production areas.

Phoenix tail bamboo

Native to China, it is now planted in batches in the warmer regions of southern China.

(Phoenix tail bamboo)

Common diseases of Hawaiian bamboo

Brown spot disease

This disease harms the leaf part of the plant and is greatly related to watering. The specific prevention and treatment method is: during its growth period, water appropriately; it is better to let the flower soil be a little dry than to let it be too moist. If watered too much, it will cause the leaves to rot or wither and yellow, affecting the ornamental degree. In addition, when the air in summer is relatively dry, water 2 to 3 times a day to ensure that the branches and leaves can grow vigorously.

Downy mildew

To deal with this disease, first remove the leaves that have already become diseased, and then spray some disinfecting medication.

In addition, light should also be given appropriately to increase the plant's disease resistance. It is a green plant and needs the care of sunlight, but direct light should be avoided. If the leaves are exposed to the sun, the leaves will turn pale yellow or directly wither, which will harm the plant even more. At the same time, it is also very shade-tolerant, so when the plant has just entered the growth stage, it is best to provide some shading protection and not let the plant be directly exposed to sunlight.

For Hawaiian bamboo, the main harm is anthracnose. Below is a detailed introduction to the symptoms and prevention and treatment methods of anthracnose.

Anthracnose

Symptoms

On the leaf surface of Hawaiian bamboo, small round brown spots appear, which later gradually expand into oval and spindle-shaped spots; when they occur on the leaf edge, they become half-spindle-shaped. The lesions have a dark brown wide border and a grayish-white center, and later small black dots are scattered on the lesions.

Occurrence pattern

The pathogen is a fungus, Colletotrichum. The pathogen overwinters in diseased leaves on the plant and in diseased residues that fall to the ground. In the following spring, when temperature and humidity are suitable, it produces conidia, and during the growing season, it spreads many times through wind and rain for repeated infection. In greenhouses, it can occur year-round. When it is warm and humid, dew lasts a long time, and there are many rainy days, the disease is prone to epidemic. When environmental conditions are unsuitable for plant growth, soil fertility is poor, and growth is weak, the disease often occurs severely.

Prevention and treatment methods

(1) Strengthen cultivation management. Remove diseased leaves and old leaves of Hawaiian bamboo in time, and bury them deeply in a concentrated place. Pay attention to applying more phosphorus and potassium fertilizer and organic fertilizer to enhance the plant's disease resistance.

(2) In the early stage of the disease, spray 1:2:200 Bordeaux mixture once every 15 days, for a total of 2~3 sprays. You can also spray 75% chlorothalonil wettable powder 600 times solution, 36% thiophanate-methyl suspension concentrate 800 times solution, 50% mixed sulfur suspension concentrate 500 times solution, 50% iprodione wettable powder 1500 times solution, 40% captan wettable powder 400 times solution, etc., once every 15 days, for a total of 2~3 sprays.