Answer: Okra may be picked anytime after blooming because the fruit doesn't ripen per se, but gets larger and eventually tougher. You want to let it get as large as possible without getting tough.
Varieties differ in the best size to achieve this goal, but a good rule of thumb is to pick them at about 4" long. If the pod breaks apart cleanly when you bend it, it should be tender. Older, tough pods will crack like a semi woody stick with the tough fibers hanging on!
Thanks for the question.
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