leaf out

leaf out

Of a plant, to sprout and open leaves. Something must be wrong with the tree, because it's nearly May and it hasn't started leafing out yet. Your plant may not leaf out if there is too much direct sunlight on it throughout the day.
See also: leaf, out
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

leaf out

[for a plant] to open its leaf buds. Most of the bushes leaf out in mid-April. The trees leafed out early this year.
See also: leaf, out
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in periodicals archive ?
And if all that fails, just take a leaf out of Mafia classic, The Godfather, and rest a horse's head on the penalty spot.
To be fair to Moore, the horse has now run virtually identical races on his last four starts and it might be an idea to take a leaf out of Fortune's book for the five-year-old's next outing.