Pedir peras a un olmo

Pedir peras a un olmo
 

Como se diría en inglés "Pedir peras a un olmo"? Creo que no necesita explicación. E simposible que un olmo (elm) de peras : It´s like to ask for the impossible.

To bark up the wrong tree.

I think that would be " llamar a la puerta equivocada"

poli examples looks good to me.
LLamar a la puerta equivocada - "To call the wrong door" ?

You can't get water out of a stone.
You can't get blood from a turnip.

Con las frutas:)

You can't make apple pie with pears

Maybe......

You reap what you sow

sí en inglés hay,

To bark up the wrong tree


No vendo las drogas! Your barking up the wrong tree (llamas a la puerta equivocada)

Y que tal: "you can't expect pears from an elm tree".

Saludos, t.

@Elaina: I might be confused, but as I understand, "you reap what you sow" means that if you do something now, you will have face the consequences in the future. But "pedirle peras al olmo" is rather that you cannot expect a fruiful outcome from unsuitable circumstances.

¿Esperabas que Juan corriera 100 metros en 2 minutos? No le pidas peras al olmo, ya tiene 65 años.
Did you expect Juan to run 100 meters in 2 minutes? You can't expect that much, he's already 65 years old.

Pedirle al Presidente que no mienta sobre la situación económica es pedirle peras al olmo.
Asking the President not to lie about the economic situation is asking too much.