i've submerged plants in the regular 3% H2O2 from the drugstore for up to a half hour (when they had rot) with no apparent ill effect. when i'm just repotting, i'll dunk 'em for a few minutes, but that's mostly because i'm impatient.

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"Apart from the utility of binomials for standardizing reference for effective communication,
Laelia Speciosa is a tad easier to pronounce and spell than its Atzec name
chichiltictepetzacuxochitl."
--Alec Pridgeon