Troubleshooting
Moor Witch Purple Moor Grass problems — and how to fix them
Moor Witch Purple Moor Grass (Molinia caerulea 'Moorhexe') is generally low-drama, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Chlorosis on alkaline soils
Yellow, pale foliage indicates iron or manganese deficiency caused by high soil pH; apply a chelated iron feed (sequestered iron) and acidify the soil with sulphur chips or ericaceous mulch.
Failure to thrive and die-back in drought
Unlike some ornamental grasses, Molinia does not tolerate prolonged dry conditions well; if the root zone dries out repeatedly the plant declines; mulch heavily to conserve moisture and water regularly in summer.
Prevent moor witch purple moor grass problems before they start
Most moor witch purple moor grass issues are care-mismatch, not bad luck. Dial in the basics:
Moor Witch Purple Moor Grass problems — FAQ
Why is my moor witch purple moor grass chlorosis on alkaline soils?
Yellow, pale foliage indicates iron or manganese deficiency caused by high soil pH; apply a chelated iron feed (sequestered iron) and acidify the soil with sulphur chips or ericaceous mulch.
Why is my moor witch purple moor grass failure to thrive and die-back in drought?
Unlike some ornamental grasses, Molinia does not tolerate prolonged dry conditions well; if the root zone dries out repeatedly the plant declines; mulch heavily to conserve moisture and water regularly in summer.