Plants, in general, represent knowledge, ideas, and intellectual concepts -- things of the mind. Plant the best and most beautiful of those in one place, give them plenty of water (truth from the Lord about day-to-day things), plenty of sunlight (the Lord's wisdom) and warmth (the Lord's love), tend them to keep the weeds (false ideas) out, and you get a garden. So it makes sense that a garden in the Bible represents the intellect, where with proper care we can nurture the best and most useful ideas and ways of thinking.

(Riferimenti: Arcana Coelestia 98, 100, 1588; Heaven and Hell 111)

98. Verse 8 And Jehovah God planted a garden in Eden, from the east, and there He put the man whom He had formed.

'Garden' means intelligence, 'Eden' love, 'the east' the Lord. 'A garden in Eden, from the east' therefore means celestial man's intelligence which flows in by way of love, from the Lord.