Time for a handy comparison. Here’s the full saying:
El perro del hortelano, ni come ni deja comer.
The farmer’s dog, it does not eat nor let others eat.
Dogs do not eat vegetables, nor do they let other animals (or thieves) take them from the orchard, so there you have it. We use this expression when somebody is taking for themselves something they are not profiting from anyway. Not just hogging, but also not using what you’re keeping for yourself.
And if you’ve been paying attention to my posts, you know very well by now that the second part is almost never said:
Mi hermano no usa casi nunca el coche, pero tampoco me lo presta, ¡es como el perro del hortelano!
My brother rarely uses his car, but he won’t lend it to me either, he’s like the farmer’s dog!
No seas perro del hortelano, si no estás viendo la tele, ¡déjame cambiar de canal!
Don’t be a farmer’s dog, if you’re not watching TV, let me change the channel!
Originally published in Talk like a Spaniard.