Your plan reminds me of a scene from the film
el Cid where the Christians are besieging the Moslem town of Valencia. The encirclement is supposed to have lasted around nine months. When
el Cid (Charlton Heston) was about to launch the final assault on the starving townsfolk, the Spanish wheeled up their catapults, but instead of throwing stones they tossed hundreds of loaves of bread over the walls. Naturally, the starving townsfolk rose up in revolt against the Jihadist garrison, tossed their king from the parapets, and opened the gates to the Spanish.
And I have no idea whether this actually happened.
An actual event, first recorded incident of germ warfare, gave all the moorish girls yeast infection. They knew the spics couldn't care less.