S. R. Faruqi:

The simile is new, and was so much to Mir's taste that he kept on using it throughout his life. From the second divan [{783,7}]:

yuu;N baar-e gul se ab ke jhuke hai;N nihaal-e baa;G
jhuk jhuk ke jaise karte ho;N do chaar yaar baat

[from the weight of the roses, nowadays the plants of the garden have bent in such a way,
the way, repeatedly bending, three or four friends would talk]

From the third divan [{1199,3}]:

ham bhii to fa.sl-e gul me;N chal to ;Tuk paas bai;The;N
sar jo;R jo;R kaisii kalyaa;N nikaltiyaa;N hai;N

[let's us too, in the rose season, go and sit together for a bit
repeatedly bringing their heads close, how the buds emerge!]

From the sixth divan [{1865,5}]:

bahaar aa))ii gul phuul sar jo;Re nikle
rahe;N baa;G me;N kaash us rang ham tuu

[spring came, roses and flowers emerged with their heads together,
if only you and I would remain in the garden in that style/manner!]

With regard to meaning, the verse from the third divan appears to be the best; but in its expression there's not as much clarity as there is in the present verse. In niklii hai;N ab ke kalyaa;N there's also an implication of the turmoil of the spring-- that is, in the spring it's not every time that there's such thickness and abundance of the buds.

[See also {1507,1}.]

FWP:

SETS
MOTIFS
NAMES
TERMS == SIMILE

It truly is a lovely image, isn't it? The densely growing roses swaying their heads toward each other in the breeze, and then away again, only to converge once more. The casual, careless, swaying movement is a large part of the charm. Good friends are relaxed when they sit together, they change their positions with informal ease; they often bring their heads together to exchange confidences; then their heads often sway back again as the friends are overtaken by laughter or surprise at some shared bit of gossip.

Note for grammar fans: In the first line ab ke modifies a colloquially omitted vaqt (or mausam ?).

Note for meter fans: 'Buds' is of course kaliyaa;N , short-short-long, but for scansion purposes it here has to be read as kalyaa;N , long-long; this is a permissible variation.