@K_A  
(To be clear, “relative to the planet” refers to the frame of reference of the sun “moving,” in case someone tries to be cute by bringing up basic real-life astronomy.)

@Roxor  
Earth ponies are the only ponies that grow crops. Yes, I realize that the difference between an earth pony and a pegasus tossing seeds in a ground and tending it should not otherwise exist, and that is yet to be filled by explanation. It’s not hard to justify it with the point on enhancement you bring up: the soil is relatively infertile and requires earth-pony magic (and similar magics in other species) for new life to sprout and prosper. One can also argue they also are able to figure out esoteric lore to produce magical crops such as the odd ceremonies Granny Smith did to raise zap apples.
 
Obviously, plants thrive in Everfree explicitly without pony influence, and other species clearly do not have that limitation. Vampire fruit bats sprout up stronger trees by spitting out sucked-up apples. (IMO, however, “Bats!” may as well be titled “Why Earth Ponies Are Incompetent and Should be Replaced by Fluttershy,” and is a centerpiece to my complaint in the first place….)
 
Don’t forget that we have two totally-not-goddess ponies responsible for moving celestial bodies around relative to the planet. That’s kinda something expected to happen on a thriving earth-like biosphere without ponies around.

@K_A  
And if only earth ponies can grow plants, then how do they grow in places where there are no earth ponies, like areas of wilderness far away from pony civilisation, out in the ocean or before ponies evolved?
 
My point is that the idea that only earth ponies can grow food seems badly thought-out.
 
Now, earth ponies enhancing the growth of plants, I have no problems with. It makes perfect sense that they’d gravitate towards farming with such an ability, but outright requiring them for plants to grow raises problems.

@Roxor  
What is your point? It should be bleedingly obvious I meant food for other ponies, i.e., vegetation.
 
Are you trying to defend bad fanon?

@K_A  
ONLY earth ponies can grow food? That doesn’t make sense when damn near everything is food for something else. Plants are food for herbivores, herbivores are food for carnivores, and carnivores are food for bigger carnivores.

@K_A  
(That’s general earth pony magic that’s not necessarily food-related, although we know Maud knows how to draw at least flavoring agents from rocks.)

That earth ponies are magic is basically canon, but their unique skill in raising food has been handwaved very often in both the show and especially by some fanfiction (Fluttershy suddenly having a garden or small-scale farm being a criminal offender). It wasn’t until Maud Pie showed supernatural skill in rock-smashing that it really got to manifest.