Maaseh Shabbos 5

(2) If one plants etc. he should uproot it - which is not the case by cooking since you can't uproot what you cooked, so too by maaser since it was already fixed according to the Torah [meaning that since on the Torah level his produce has been properly tithed that cannot be undone.]

(19) If one plants on Shabbos by accident, he may leave it, though if he did so intentionally he must uproot it: unlike by cooking which cannot be uprooted. Even though he can throw the cooked food into the sea, the Chachamim did not want to destroy items that are permitted, just to nuliffy the forbidden action where possible...

...and you should know that the opinion of the Shulchan Aruch who holds like Rabbi Yehuda that if one transgressed by mistake it is permitted to benefit from it after Shabbos, this is by all the melachos where it is visible that there is a penalty imposed by Chazal not to have benefit from it on Shabbos, until after Shabbos. Though if one plants a tree on Shabbos or puts seeds into the ground, where even without the penalty he cannot have benefit from it right away, doing so by mistake is the same rule as doing it on purpose, by both you need to uproot the sapling. This is explicit in Gitten 54b in the opinion of Rabbi Yehuda see there.

(4) forever - to have benefit from that melacha, for the Rabanan penalized him. Though either way it is permitted for him to have benefit from the monetary value of the melacha....

...In truth, that which it is permitted to have benefit from the value of the melacha it would seem that this would mean that you can sell it only for the value that it was worth before you did the melacha in order that you do not derive benefit from the melacha done on Shabbos, for if not what does the penalty accomplish?