**Yes, this is a real quote by Vincent van Gogh (although translated).**
It is included in the page for Vincent van Gogh on Wikiquote, which is generally a good resource for verifying (alleged) quotes.
As found on Wikiquote, the quote was written by Vincent van Gogh in a letter to his brother, know as 'Letter 22'. The full letter is available online, including facsimile, transcription, and translation.
The letter was written in Dutch, so the quote as posted in the question is a translation of the original, which is as follows:
> Als men waarachtig van de natuur houdt dan vindt men ’t overal mooi.