Answer: Mullein has a deep taproot so transplanting large plants will be iffy. However, if you can find some really small specimens and you dig deep, you should be able to transplant them. Failing that, you can collect seeds from spent flowers. Look for tannish colored seed pods just behind the shriveled petals. Collect the seeds and sow them in your garden this summer, then thin out the seedlings as they emerge next spring.
Best wishes with your garden!
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