Although many kinds of herbs will go to seed afterwards, I like seeing my various herbs flower. Some herbs will die down after flowering. Others won't. However, seeds from the old plants can then produce new plants. Life continues to renew.

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As for Mint Specifically
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REMOVE the flowers from your mint if:

* You want to be able to harvest as many leaves as possible
* You want the plant to continue growing bigger
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ALLOW your mint plant to flower if:

* You don’t or rarely harvest and use the leaves.
* You prioritize having beautiful flowers over being able to harvest as many leaves.
* You want to use or eat the flowers (in that case, harvest them when they are at the point you want)
* You want to collect seeds.

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I deliberately allow my mint and other herbs to flower.