Plants don't grow because someone is watching, and Dickinson insists that people don't either. The poem makes one claim and circles it for sixteen lines: real growth, whether of a tree or of a human being, happens inside, slowly, and without applause. Sun and air may be present, but the work belongs to the thing that is growing.
The first line sets up the comparison, and the second makes it strange. Growth normally suggests reaching up and out, yet here it "Gravitates within," a verb of pulling toward a centre. It is less a flourish added from outside than an inward weight, a settling into oneself. The outer world is demoted to match: "Atmosphere, and Sun endorse it." To endorse is to sign off on something already decided, so the weather approves but does not cause. The stanza's last line is printed here as "Bit it stir -- alone." This looks like a slip for "But it stir," which fits the sense: whatever the sun approves, the stirring is done alone.
The second stanza names the stakes. Each living thing has a "difficult Ideal" that it "Must achieve -- Itself." The line can be read two ways. The thing must achieve its ideal by itself, unaided, or it must achieve *Itself*, become what it is meant to be. Dickinson doesn't choose, and the capital I makes the growing thing a character, a self with a task. Then comes the surprising phrase "solitary prowess." Prowess is a word for knights and athletes, and she gives it to "a Silent Life." This is heroism with no trumpets.
The third stanza says what the heroism consists of. "Effort," "Patience," and "Belief" are oddly undramatic qualities. Effort is called "the sole condition," though three are listed, as if they were one demand seen from different sides. The patience is double-edged: "Patience of Itself" may mean patience with oneself, and "Patience of opposing forces" may mean putting up with resistance, or perhaps the steady endurance of the resistance itself. "Intact Belief" is the quietest and hardest phrase. Intact implies that something is pressing on belief, and the task is to keep it unbroken.
In the last stanza the vocabulary turns official. The audience has a "Department," as though watching were a government office with a narrow remit: "Looking on." Growth, meanwhile, is a "Transaction," a piece of real business that is "assisted / By no Countenance." Countenance means a face, but also encouragement or approval, so the line says that no friendly look, and no nod of support, takes part in the exchange. Spectators can stand at the edge, but they cannot do the work.
The form suits this stubborn privacy. Four short quatrains, lines of only a few beats, and Dickinson's dashes break the sentences into small steps, so reading the poem takes a little effort of its own. Rhyme is almost absent. The ear catches only faint echoes, such as "Itself" and "Belief," or "Audience" and "Countenance," and "Itself" itself ends the second line of two stanzas in a row, as if the word were the poem's anchor. The capitalised abstractions (Effort, Patience, Ideal) have the same effect as the vocabulary of offices: they make inner qualities feel like solid objects.
Dickinson lived in Amherst, Massachusetts, and most of her poems went unpublished while she was alive. It is tempting to hear that fact echoing in a poem about unwitnessed effort, though the poem itself never says so and should not be forced into a biography.
What makes the poem lasting is its refusal to comfort. It never says what the Ideal is, shows no finished flower, and promises no success. It says only that growth is difficult, lonely, and unobserved, and that this is how it works. For students, that may be its most useful point. The visible results of learning, such as grades and praise, come from a process that happens where nobody can see it.