Asparagus rust is characterized by different color spots or pustules on spears and fern branches. Orange
pustules are present on new spears in spring and brick red pustules develop on stalks, branches, and leaves
in summer. Black spores are present in fall and winter. Fern yellowing and browning, defoliation, and
dieback may occur.
Rust is most prevalent in more humid areas. Provide adequate irrigation during the spring and summer
fern period so that the plants are neither over- or underwatered. Sulfur and other fungicides applied
when rust first occurs are helpful in control. Cut down diseased ferns at the crown and destroy. Resistant
varieties may be available.
asparagi on asparagus spears