The poet personifies nature with a commonly used term as emother naturef and I think the hidden meaning behind this is that the poem he has written carries the same message that has been preached for years, yet no one bothers to follow or listen to it.
The poet says gnaturefs first green is goldh he compares the colour of nature egreenf with something that can be bought i.e. gold. Maybe he is trying to say that naturefs first baby is green that is just as valuable as gold but the he says gher hardest hue to holdh which might mean that green was her hardest hue to hold as it was the most valuable just like gold and it would be taken away from her.
gca flowerh flower symbolises purity, beauty and nature just like a new born baby, and when the poet says gher early leaffsch it proves that he is talking about something just born or created. However, he then says, gbut only so an hour.h which makes evident that the beauty and innocence will only stay for an hour and then fade away. gEden sank to griefh, the Garden of Eden has always been symbolic of Adam and Eve and the forbidden fruit, so the poet probably wants to say that naturefs first flower, i.e. Adam and Eve were innocent and pure but after a certain time, they too were tempted by the fruit and they had to come down to earth and thatfs why Eden was angst. gcdawn goes down to dayh just like dawn