What is this?

Saluda, SC(Zone 8a)

The large plant in the first photo ( Zebrina Malva sylvestris Hollyhock Mallow Plant) was a beautiful lush looking flower. Suddenly the older leaves developed yellow bumps and spots (like the 2nd photo) and are dead.

What is happening? These plants are reseedlings from an heirloom that was on the lot when I first moved here many years ago, so I prefer to save it if I can. Can this be treated or should I just destroy these plants?

Thumbnail by gessieviolet Thumbnail by gessieviolet
Charlotte, NC(Zone 7b)

Hollyhock Rust Fungus, perhaps?

http://www.ipm.iastate.edu/ipm/info/plant-diseases/hollyhock-rust

Kure Beach, NC(Zone 9a)

Yea, that is not happy!
I have that plant and love it. It does look like a fungus. I read the link Honeybee posted. I hope you have some plants that aren't affected or at least some seeds since it doesn't seem like it's easily treated.
Barb

Saluda, SC(Zone 8a)

These just come back from seeds year after year. These 3 plants germinated late last summer and survived so far. I should be seeing more little ones shortly in other areas of the yard.

(Zone 9a)

If it is indeed a fungus (your extension office should be able to tell) you might want to "clean up" that area in your yard so the fungal spores do not hang around. I would rake up every leaf and twig to prevent the re-occurrence.

Greensboro, NC(Zone 7b)

I'm afraid that is rust, particularly if it's on a hollyhock. The Malva family is particularly susceptible. I found that out doing my own research on this terrible thing a few seasons ago. I had to pull my HHs out because I could not control the spread.

Last season I grew Malva zebrina from seed and to avert disaster I continued to cut lower leaves from the plant as it got taller. The fungus is spread in rainfall where it transfers by splashing from leaf to leaf. You can cut the plant down entirely so you can treat the plant from the ground up. You can purchase something chemical to control it. I don't use chemicals in my butterfly garden, so this was not an option for me. I found that pruning the foliage back was successful with the Malva.

This year, I have some HH volunteers at the back of the yard. I believe that the fungus is also encouraged by too much moisture in the soil. The HH wants dry soil and should be in completely FULL SUN conditions to discourage the spread of this disease. Remove all mulch and leaves/debris from around the base of the plants and allow soil to completely dry out. Keep the diseased foliage pruned back. Prune with a CLEAN blade. Don't pass the fungus from plant to plant. Completely dispose of the diseased foliage. Careful not to release more spores into the air around your plants, but not all plants are susceptible to rust.

Hope this helps.

A.

Saluda, SC(Zone 8a)

Thanks Amanda. Boy, I got hollyhocks for the first time! They are well away from this malva so I am hoping.

Greensboro, NC(Zone 7b)

Best of luck dearie. It broke my heart to discard those HHs. I brought them with me to this new house from my old condo and some of them were probably 10 years old. I didn't loose too many plants, but still.... Calamity.

I'll hope for the best for you!

A.

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