Rust

Orange to rust-brown pustules that rub off as colored powder on your finger — that powder-smear is the confirmation. Undersides of leaves first, then yellowing tops; roses, hollyhocks, beans, and daylilies all keep their own versions.

Disease34 plants we cover get rustmostly perennials

Disease checklist

Four things to look for. If most of them match what you are holding, you are in the right place.

Orange to rust-brown pustules on leaf undersides
The powder rubs off onto your finger
Yellowing on the upper leaf above the pustules
Roses, hollyhocks, beans and daylilies

What gets rid of it

Gentlest option first. For most backyard cases the first one is enough, so try these in order and stop as soon as it works. If you do spray something, the product label tells you how — please read the notice further down.

1Strip and destroy infected leaves
Every pustule is releasing spores; picking visibly rusted leaves — and raking fallen ones — cuts the reinfection loop.
Try this first
2Keep leaves dry
Water at the base in the morning; rust spores germinate in standing leaf moisture.
3Sulfur or copper fungicide
Protective sprays for plants with a rust history, started before symptoms per the label.
sulfur fungicide garden

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Which plants get rust

Every plant we cover that gets rust, grouped by type — tap any one to open its page. A note beside a plant came from that plant’s own entry, because the same disease can be a minor nuisance on one plant and a serious problem on another. Plenty of plants we do not cover get it too.

trees3

shrubs9

perennials10

biennials2

annuals5

bulb1

GarlicAllium sativum

grasses4

Plant families hit hardest

Related plants often share the same problems, so if one plant in a family has it, check the others. The largest group here is Poaceae, with 5 of the 34 affected plants.

Poaceae5 plants
Rosaceae5 plants
Asteraceae3 plants
Malvaceae3 plants
Amaryllidaceae2 plants
Berberidaceae2 plants
Grossulariaceae2 plants
Lamiaceae2 plants

When to treat

Treat at the first pustules and clear infected leaves. It spreads through the wet part of the season.

On specific plants

Blackberry
Dormant
Lime Sulfur: Late winter (Delayed Dormant) to clean up Anthracnose/Rust spores on canes.
Eastern White Pine
Growing
The currant conflict is real: Ribes within a few hundred yards sustains rust cycles.
Hollyhock
Growing
Remove rust-spotted leaves; choose rust-tolerant strains.
Leek
Growing
Rotate alliums; rust rarely needs action in home beds.
Marshmallow
Growing
Improve airflow; remove rusted leaves.
Quince
Dormant
Copper at bud swell where fireblight or rust has history.
Snapdragon
Growing
Rust-resistant varieties; water at the base.

Timing only — the label is the law

This page tells you when to watch for rust and when treating is worth considering. It is not a recommendation to apply any particular product. Read and follow the product label before you spray — under federal law the label is the legal instruction, and using a pesticide against it is illegal.

Check the pre-harvest interval. Every product that’s cleared for an edible crop sets a minimum number of days between spraying and picking. Find it on the label before you spray anything you intend to eat.
Check the re-entry interval before you or anyone else works in the treated area again, and use the protective equipment the label names.
Confirm the product is registered for your crop in your state. This page groups many different crops together, and a product legal on one of them is not legal on all of them — state registrations differ too. Your state pesticide agency or local extension office can confirm both.
Rates and mixing instructions come from the label, never from us. We don’t publish them because they differ by product and formulation.