What to Do When Asparagus Fern Leaves Turn Yellow? Causes and Solutions

Asparagus fern (Asparagus setaceus) is a perennial evergreen climbing foliage plant, a famous ornamental plant. It is an ornamental green plant with high ornamental value; grown indoors, it can also purify the air, kill bacteria, and help regulate indoor air. When growing asparagus fern, what should you do if the leaves turn yellow or even dry up and drop off?

Yellow leaves caused by too much light

Asparagus fern likes partial shade and dislikes strong light, especially in summer, when it must be kept out of direct sunlight, otherwise the branches and leaves will turn withered and yellow. Move the pot to a shady spot and mist the branches and leaves frequently to increase air humidity.

Yellow leaves caused by improper watering

Asparagus fern likes moisture but fears waterlogging; keep the potting soil alternating between dry and moist, and generally just water enough to moisten the topsoil. Too much water easily causes root rot, while too little causes dry leaf tips, so in dry seasons spray the leaves with clean water frequently.

Yellow leaves caused by improper fertilizing

If a top dressing is applied too concentrated or with un-decomposed fertilizer, it easily causes “root burn”, leading to dried and falling leaves. Conversely, if the potting soil is poor, the leaves will also turn yellow from a lack of nutrients.

Yellow leaves caused by poor winter care

Asparagus fern likes warmth and should be kept in a sunny spot in winter. If it is kept for a long time in a place with no light in winter, or with poor ventilation or cold, the leaves easily turn withered and yellow. Generally, the room temperature should be no lower than 12°C, and the plant should be placed near a south-facing window with watering appropriately controlled.

Yellow leaves caused by poisoning

Asparagus fern is sensitive to smoke and dust; if it is exposed to toxic gases, the branches and leaves easily turn yellow. In addition, if the plant is too large for too small a pot, or if it is harmed by pests such as scale insects, the branches and leaves will also turn yellow, so it should be repotted and treated promptly.

Yellow leaves caused by pest and disease infection

Once asparagus fern is infected by pests such as scale insects, the branches and leaves will also turn withered and yellow, so it should be treated promptly.

If the asparagus fern is not growing very lushly, it should be fertilized. Here is a folk method: watering the asparagus fern with white sugar water can also help add nutrients. Watering it with 5—10% white sugar water every 20 days is enough to make it grow lushly.