So the last two lines are repeated from the beginning of the poem, Since this is the last lines of the poem then I see this as maybe the rest of the poem was his vision or dream of what he sees through the open shears in the garden. The gardener was using his imagination through his own lenses of how he may see his own fragile life. Maybe he is bored or needs to sort through his own views of life. Since he is a gardener he could see himself as a lower statue in life because he works for royalty and feels he is a nobody. Many times nobility will treat those that are not as elite like they don't matter. Many times I see this in the wealthy in our own lives or see how put others down who are poor or from other countries.

Ok it talks about the true prince walking in unharmed well I understand what this is talking about because I decided to read the Grim's Fairy tale we have, So the reason that the prince went in to the brier's unharmed is because now all the roses have bloomed so he could get past the thorns. The other princes's if maybe tried hard enough to get through. You would think after the first one died the others ones would get a clue. The true one was willing to wait all these years for the roses to bloom. The second line learned to make a study of the hour could relate to this, that he studied the right time to enter.

Yes I get that . All the time when people are socializing or trying to get to know other people, they always ask what do you do? So people see you as that and label you and if what you do sound uninteresting to them they go on to someone else that sounds more fascinating. What you do for a job does not define you.