What are the control methods for leaf spot disease in calla lilies?

Yellow-brown spots appearing on calla lily leaves not only affect their appearance and spoil your mood, but in severe cases can kill your little calla. This article introduces the symptoms and control of leaf spot disease for you!

Symptoms of leaf spot disease in calla lilies

When the disease occurs, light brown or yellow-brown spots appear on the leaves, mostly round, oval or irregular in shape. A few show very faint concentric rings. In the later stage, the spots gradually merge, forming many black mold-like substances, which are the conidia of the pathogen. If not treated in time, they will spread to the entire plant... Pathogen and disease pattern Leaf spot disease is a fungal ☆ban☆ disease caused by fungal infection. This pathogen is rather stubborn; it overwinters in the diseased leaf debris of calla lilies and spreads through airflow.

High indoor temperature and humidity will accelerate the spread of the disease, with the most severe damage occurring from July to October each year. In winter, when the plant is kept indoors, once the temperature reaches 18-20 degrees C, the disease can continue to spread, and diseased plants become a source of infection.

Under poor ventilation or extremely poor care conditions, the disease incidence is more widespread.

Control methods

Strengthen cultivation management

According to the habits of calla lilies, place them in a shaded and ventilated location to reduce disease occurrence. If placed directly in sunlight, it will weaken the plant's growth and lead to disease. In winter, place calla lilies on the north side indoors.

Water and fertilize reasonably to promote vigorous plant growth and improve disease resistance.

Promptly remove sources of infection

Once diseased and remnant leaves are found, remove them promptly. Before moving indoors in winter, thoroughly remove diseased leaf debris, loosen the soil appropriately, keep the pot soil surface clean, and reduce sources of infection.

Chemical control

When the disease is relatively severe, chemical treatment can be used. In the early stage of the disease, carbendazim can be diluted into a 1000-fold solution and sprayed, once every 15 days, 3 consecutive sprays being sufficient.