I have two indoor experiments happening with my garlic. This one is hydroponic (kratky method) and the there in soil.
Soil version is going great!
The hydroponic started off nicely, yet this is happening now. Nutrients started as 10-10-10 in the hydro test, 30-8-6 in the soil (just learned the mix).
I did up the Nitrogen to match the soil experiment and may have over done it..
It looks like you nailed the problem, too much nitrogen for hydro growing of garlic.
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