瓜熟蒂落，水到渠成

瓜熟蒂落，水到渠成

Literally means:

when a melon is ripe, it falls off its stem; when water flows, a channel naturally forms

Actually means:

when water flows, a channel naturally forms; when conditions are ripe, success comes naturally

蒂, the part connecting a melon or fruit with the branches or vines; 落, fall off; 渠, channel.

This phrase literally means when a melon is ripe, it will naturally fall off its stem and when water flows over, a channel will naturally form. It figuratively means when conditions are ripe, success will be attained naturally.

蒂，瓜果与茎枝相连的部分。落，脱落。渠，水渠，渠道。

瓜熟蒂落，水到渠成，瓜成熟以后，瓜的蒂自然就会脱落，水流过来，渠道也就自然形成了。比喻条件备以后事情就会顺利地办成。