Fight the Fungus: How to Recognize and Treat Fig Rust
Updated: 7 days ago
Want to make your garden stand out? Grow a fig tree! With their delicious fruit and beautiful foliage, fig trees are a favorite among gardeners and fruit tree enthusiasts. But, beware! Just like many plants native to dry and warm climates, fig trees can be prone to a fungal infection called rust in areas with high humidity. Don't let rust ruin your fig tree's beauty and productivity. Learn how to recognize and address this fungus before it causes significant harm. Remember, prevention is always better than reacting when it comes to fungal issues. Keep your fig tree healthy and fruitful, take action now!
Fig trees are a desirable addition to any property due to their tasty fruit and attractive foliage, making them a favorite among many gardeners and fruit tree growers, but when grown in humid climates, fig trees are susceptible to fungal infections, specifically rust, when grown in areas with high humidity.
Rust can be identified by small yellow spots on the upper surface of the leaves, which grow larger over time and turn a reddish-brown color.
Rust typically appears during late summer and in severe cases, it can cause the fig tree to lose its leaves in a matter of weeks, which can have a significant impact on the tree's growth and yields, as well as its overall health.
Preventing rust is the best way to avoid the problem in the first place by using techniques such as proper fig tree pruning, regular cleaning of leaf litter, use of fungicides, and keeping your tree dry and by using special soil nutrients like silica.
Check out my video on fig tree rust for additional information:
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Identifying Fig Rust
The early signs of fig rust are small yellow spots on the upper surface of the leaves. These spots, also known as lesions, will grow larger over time and turn a reddish-brown color, but they tend to remain relatively smooth. On the underside of the leaf, the lesions will have a reddish-brown color and a slightly raised blister-like appearance. When the infection is severe, the leaves will turn yellow or brown, particularly around the edges, and fall off the tree prematurely.
Rust typically appears during late summer and in severe cases, it can cause the fig tree to lose its leaves in a matter of weeks. This can have a significant impact on the tree's growth and yields, as well as its overall health. If defoliation occurs regularly, the tree's growth may be reduced and yields may be affected due to a loss in photosynthesis.
Reach the end of the article for more leaf problems that affect fig trees and what they look like.
Why are My Fig Tree Leaves Turning Rusty?
Fig rust is caused by a fungus called Cerotelium fici, which thrives in warm and moist environments. The fungus infects the fig tree through its leaves, making other leaves on the tree and neighboring fig trees more easily infected with rust if conditions continue to be wet and humid. For example, one droplet of water that carries the fungus can spread fig rust to other leaves and other trees.
Does Fig Rust Go Away?
Fortunately, fig rust can seemingly go away on its own. In dry years, fig rust is not observed in my Philadelphia area climate. While in wet years, growers in the humid mid-Atlantic or Southern United States can see severe infections of fig rust. In these climates, a severe infection occurs almost every growing season.
In dry places like most of California, Arizona, or West Texas, rust is something you'll almost never observe. Even if you received a tree with rust on it, the fungus will not spread and the following year after a period of dormancy reveals no trace of rust whatsoever.
Fig rust is worth worrying about in places where severe infections can occur. For the rest of us, you can sleep easy knowing that everything will be fine.