TrojanBird wrote:Well, could you say りんごができる like in the sentence to mean "to be able to grow apples"?
I don't think so. Here's a somewhat long explanation of why not:-
The verb する doesn't have a potential form. This is a bit like the English verb "to go" in that "to go" doesn't have a past tense: when we need to put "go" in the past tense, we use the past tense of a different verb--the verb "to wend" means much the same as "to go" and its past tense is "went", so we use that for the past tense of "to go". Similarly, できる means "able to do" and so is used as the potential form of する.
However, できる has other meanings in addition to "able to do". It also means to be made, to be built, to be raised and to grow. So できる isn't always the potential form of する--often it's used because it has those other meanings. In the sentence 「オレンジは暖かい国でできる」, できる is being used for one of its other meanings and not as the potential form of する.
マイケル