Rashi: It is a rose.

Malbim (Mashal): It is vegetation whose roots are under the ground, like onions. They do not have a strong smell. They have a very nice flower on top. It opens in front of the sun and leans towards it, and closes when the sun sets. It grows and succeeds only in Sharon, in front of the sun.

Seforno: The commoners give a nice scent via fulfilling some Mitzvos.

Malbim (Melitzah): The Nefesh says, I remove my filthy garments, and leave the valley and holes (dwelling in the body) to the Sharon, to be warmed in the light of the great sun - Hashem's light shining on me. Chavatzeles ha'Sharon opens its flowers, buds and sprigs to swallow the sunlight and lean after it. Then it is seen in its beauty. So when the sun of Elokus will shine on me, the Nefesh will spread and send out its spiritual flowers and reveal its upper arms (Divinity hidden in it), and its beauty will be seen.

Malbim (Mashal): I love rest, to dwell in Sharon and open my beautiful flowers in front of the sun that shines there, to give my beauty ¹ in front of my beloved, who shines like the sun in Sharon in the Midbar, and makes his light appear on me.

Rashi: It is nicer than mountain roses, for it is always moist, for the sun's strength does not rule [in valleys].

Seforno: It grows among thorns. So I cling to You even at a time of mishaps. We request that Hashem go among us.

Malbim (Melitzah): When Hashem's honor will depart from the Nefesh, and the great sun (refer to 2:1:2:2) will set, it will close its flowers and mouth and withdraw its Divine arms. It will return to the valley (body) and emit the good scent and Ruchniyus that it received from the great light. Its neighbors, powers of the Nefesh that depends on physicality, they will absorb scent of its spikenard and put in their Kelim to learn from it Hashem's ways, conduct, Chachmah and Chasadim. Then it will resemble valley roses, which give scent under shade. The Zohar says, when it wants to mate with the king, it is called Chavatzeles. After mating, it is called Shoshanas - "Sifsosav Shoshanim" (5:13).

Malbim (Mashal): Shoshanas has a nice scent. At sundown, it emits the scent that it absorbed. Its growth and scent succeed in valley and in the shade. After I return to the valley, under the shadows (this is like Chadrei Shlomo, where she was incarcerated far from the sun of her beloved that shines on her flowers), then I emit the good scent that I received from the sun. I.e. then my neighbors Bnos Yerushalayim will sense my good smell, Musar and Midos.