Gardener credos doesn't apply Doubled yield from gardening p

[penelop]

Gardener
Can plant Blood Sterns, Farming +5
Can plant Cavebulbs, Farming +5
Halved soil and water required for gardening pots.
Can plant Chiming Bluebells, Farming +10
Doubled yield from gardening pots.

After completing the gardener credos quest , I still can't keep doubled yield from gardening pots.

[Dakkan]

Did you plant those gardening pots before or after gaining the credo bonus?

[loleznub]

Did you also fully complete the credo, so that it shows under the "Acquired Credos" section?

If it's level 5/5 quest X/X, then you have not fully completed it yet.

[penelop]

" Did you plant those gardening pots before or after gaining the credo bonus? "
If these is the reason , I know now why I can't keep doubled yield from gardening pots.
thank you for your reply.