The phrase good wine needs no bush means there is no need to advertise or boast about something of good quality, as people will always discover its merits.
It is first recorded in the epilogue to As you Like it (Folio 1, 1623), by the English poet and playwright William Shakespeare (1564-1616):
If it be true, that good wine needs
no bush, ’tis true, that a good play needes no Epilogue.
Yet to good wine they do vse good bushes : and good
playes proue the better by the helpe of good Epilogues.
Here, the noun bush denotes a branch or bunch of ivy formerly hung as a vintner’s sign in front of a tavern. In Florios second frvtes, to be gathered of twelue trees, of diuers but delightsome tastes to the tongues of Italians and Englishmen. To which is annexed his Gardine of recreation yeelding six thousand Italian prouerbs (London, 1591), John Florio (1553-1625), English lexicographer, teacher of languages, translator and author of Italian descent, wrote:
Womens beauty […] is like vnto an Iuy bush, that cals men to the tauern, but hangs it selfe without to winde and wether.
By metonymy, bush took the additional sense of tavern; in The fair maid of the West. Or, A Girle worth gold. The first part (London, 1631), by the English playwright and poet Thomas Heywood (circa 1573-1641), a character says:
Then will I go home to the bush where I drew wine.
In The History of Signboards, From the Earliest Times to the Present Day (London, 1875), Jacob Larwood (1827-1918) and John Camden Hotten (1832-73) explained:
The oldest sign borrowed from the vegetable kingdom is the Bush; it was a bush or bunch of ivy, box or evergreen, tied to the end of a pole […]. The custom came evidently from the Romans, and with it the oft-repeated proverb, “Good wine needs no Bush.” (Vinum vendibile hedera non est opus; in Italian, Al buon vino non bisogna frasca; in French, à bon vin point d’enseigne.) Ivy was the plant commonly used […]. It may have been adopted as the plant sacred to Bacchus and the Bacchantes, or perhaps simply because it is a hardy plant, and long continues green. As late as the reign of King James I. many inns used it as their only sign. Taylor, the water poet, in his perambulation of ten shires around London, notes various places where there is “a taverne with a bush only;” in other parts he mentions “the signe of the Bush.” Even at the present day “the Bush” is a very general sign for inn and public-house, whilst sometimes it assumes the name of the Ivy Bush, or the Ivy Green, (two in Birmingham.) In Gloucester, Warwick, and other counties, where at certain fairs the ordinary booth people and tradesmen enjoy the privilege of selling liquors without a licence, they hang out bunches of ivy, flowers, or boughs of trees, to indicate this sale. As far away as the western States of North America, at the building of a new village, or station, it is no uncommon thing to see a bunch of hay, or a green bough, hung from above the “grocery,” or bar-room door, until such time as a superior decoration can be provided.