seedlings being hardened off have stem damage..

from one day on the back patio, damage literally not there in the morning, appeared by evening

tray of 30 seedlings, 20 affected, did find 4 aphids on further inspection..

seems that the stem skin is eaten away, can't find pictures anywhere that really look like it

some leaves have stress, probably from some windy afternoons during hardening

any ideas?

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