The grass garden at Dawn Gardens in Grass Valley has about 15 different varieties of ornamental grasses planted on 1/4 acre in full sun. The grasses receive water about once a month from June to October. Many would be able to survive with no water but they all look better with some irrigation in the summer. Most of the grasses are cut back to the ground in the winter to rejuvenate the foliage for the new season. In general ornamental grasses are very low maintenance. They don't need any fertilizer, the deer don't eat them and they have few pests.