As much as you replace, they will consume. Because porcupines eat primarily wood, most people are unaware how much they like succulent plants. Porcupines love rose bushes, pansies, lily pads, all types of berries, corn, and several other garden favorites. Rabbits and deer are often blamed for this damage when many times it is being done by porcupines. Since they are mostly nocturnal, they are able to go about their business undetected.
Porcupine control is done in one of two ways.
Once you find activity, it is important to stop it early. Porcupines will travel several miles for a meal , but once they find a good place to feed, they will eat everything available before they move on. Because of this nature, you must nip it in the bud. This can be done by either removing the item they want to feed on or by making it taste terrible so they simply leave it alone. Tools, yard furniture and small wooden objects can usually be removed so porcupines will not have access to them.