Troubleshooting
'Glass Gem' Corn problems — and how to fix them
'Glass Gem' Corn (Zea mays 'Glass Gem') is generally forgiving once you match its basics, but a few issues come up again and again. Here is what each one looks like, why it happens, and the fix.
Dull or incomplete kernel colour
Results from poor pollination or stress; plant in a block, keep watering even during silking, and let cobs ripen fully on the stalk for the best colour.
Cross-pollination spoiling colour
Pollen from nearby field or sweet corn changes kernel colour; isolate by 250m or stagger planting times to keep the rainbow trait.
Corn earworm
Caterpillars feed at ear tips; apply a few drops of mineral oil to silks after pollination and remove damaged tips.
Lodging
The tall stalks blow over in wind or thin soil; hill up around the bases and avoid late nitrogen overload that weakens stems.
Prevent 'glass gem' corn problems before they start
Most 'glass gem' corn issues are care-mismatch, not bad luck. Dial in the basics:
Looking for 'glass gem' corn in general rather than its problems? Read the full 'glass gem' corn care guide — light, water, soil and feeding.
'Glass Gem' Corn problems — FAQ
Why is my 'glass gem' corn dull or incomplete kernel colour?
Results from poor pollination or stress; plant in a block, keep watering even during silking, and let cobs ripen fully on the stalk for the best colour.
Why is my 'glass gem' corn cross-pollination spoiling colour?
Pollen from nearby field or sweet corn changes kernel colour; isolate by 250m or stagger planting times to keep the rainbow trait.
Why is my 'glass gem' corn corn earworm?
Caterpillars feed at ear tips; apply a few drops of mineral oil to silks after pollination and remove damaged tips.
Why is my 'glass gem' corn lodging?
The tall stalks blow over in wind or thin soil; hill up around the bases and avoid late nitrogen overload that weakens stems.