Why are these plants turning brown? - Ask Extension
I work in Iosco County and was asked why the plants that they planted in front of the building are turning brown and look like they are dying. They ar...
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Why are these plants turning brown? #833410
Asked June 02, 2023, 3:15 PM EDT
I work in Iosco County and was asked why the plants that they planted in front of the building are turning brown and look like they are dying. They are watered daily. The location is sunny. I did notice an orange insect in one of the photos as I uploaded it.
Iosco County Michigan
Expert Response
With out any additional information (when you planted them, frost, soil nutrition, fertilizer) and only looking at the photos you provided it appears that you may have several issues with the sweet potato vines.
Possible causes of decline would be the late frost we had a week or 2 ago. Sweet potato vines are not frost tolerant. I suspect the larger brown patches on the leaves are frost damage. Trim off damaged leaves. The insect in the photo is a red spider mite. The small dots were more than likely caused by spider mites feeding the leaves. If the plants are not heavily infested, try spraying the leaves off to remove the mites. Also check and spray the undersides of the leaves. Did you fertilize the plants when you planted them? Adding a slow release granular fertilized is recommend at the time of planting (follow recommended manufacture guidelines), followed by a liquid fertilizer very 2 to 3 weeks after that.
Thank you using Ask Extension.
Pam
MSUE Master Gardener
Possible causes of decline would be the late frost we had a week or 2 ago. Sweet potato vines are not frost tolerant. I suspect the larger brown patches on the leaves are frost damage. Trim off damaged leaves. The insect in the photo is a red spider mite. The small dots were more than likely caused by spider mites feeding the leaves. If the plants are not heavily infested, try spraying the leaves off to remove the mites. Also check and spray the undersides of the leaves. Did you fertilize the plants when you planted them? Adding a slow release granular fertilized is recommend at the time of planting (follow recommended manufacture guidelines), followed by a liquid fertilizer very 2 to 3 weeks after that.
Thank you using Ask Extension.
Pam
MSUE Master Gardener
