In the context of the poem, Keats is referring to man's lust for renown, the omnipresent desire to be noticed and admired by other people. He criticizes this attitude throughout the poem, contrasting it unfavorably with the simplicity and grace of the natural world. Man is forever restless and unsatisfied; he is always striving to achieve high status in the eyes of his fellows. In contrast, look at the rose, says Keats; she still shows off her extraordinary beauty, as well as her sweet fragrance, despite living and growing in a thorny briar patch and being fed upon by bees:
But the rose leaves herself upon the briar, For winds to kiss and grateful bees to feed.
The inference is that we must live according to nature, adjust ourselves to our surroundings and our environment, and learn to be grateful for what we have. For just as a ripe palm loses its ripeness when it is taken from a tree, so too do our lives lose their beauty when they are removed from their natural habitat and disfigured by the unhealthy obsession with being popular and having a good reputation. If we can remain in our original place upon this earth and learn to live at one with nature as the roses, the plums, and the bees do, we will lead more satisfying lives.