Lupine Gardens, LLC

Pollinator Information & Gardening Tips


It’s easy to spot rust on a trowel or garden hoe. It’s that reddish-orange, flaky stuff that forms on iron and steel when they react with oxygen and moisture.

Rust is also a disease that can harm your plants. But it isn’t just one disease; it’s actually a group of fungal diseases that attack many different kinds of plants, including—but not limited to—roses, daylilies, carnations, snapdragons, mums, tomatoes, beans, pines, spruce trees and cypress. It can even attack your grass.

The first signs of rust are tiny specks or spots on leaves that range in color from orange to rusty-brown, brownish-yellow, purple and red. Left untreated, the spots get bigger and turn into bumpy-looking pustules. Eventually, the pustules break open and release spores that are spread by wind or splashing water. As they land on other plants, the spores infect them, too.

Rust isn’t usually fatal, but it can cause your plants to decline. You may see stunted growth, dead branches and yellowing leaves that drop prematurely. Lawns take on a reddish tinge, and you may stir up orange dust when you mow or walk around. 

Hot, humid weather is prime time for rust to attack, and it can be tough to eliminate.

Applying a hydrogen peroxide solution to your plants and soil can help kill off the spores and keep the fungus at bay.  You'll want to remove any plant material that is full of fungal spores. Put the plant material in a plastic bag to keep from spreading the spores and immediately burn the material. 

Hydrogen peroxide (hp) can kill molds such as powdery mildew caused by any number of fungi. It also attacks the black, sooty mold caused by aphids. When applied to the plant, the chemical's two oxygen atoms attach to the fungus and oxidize or burn it. While stronger concentrations can be purchased at garden centers containing 10 to 27 percent hp mixed with other ingredients, the household bottle containing 3 to 9 percent is adequate to kill various types of plant fungus without leaving any damaging residue. Additionally, higher concentrations (27 to 35 percent) can cause acid-like burns or other life-threatening injuries, according to the Food and Drug Administration.

Solution Mixture:

1 gallon tap or distilled water

3 tablespoons baking soda

1/2 cup 3%-5% hydrogen peroxide

1 tbsp Dawn dish soap

This solution needs to be sprayed on the entire plant and at the base of the soil to kill off the maximum amount of spores.

Rust can also be eliminated through patience. By letting nature take it's course, not watering and letting the spores die off naturally. There are organisms in healthy soil that help take care of these spores. This process can take 2-5 years to completely eliminate all of the fungus matter.