North Florida has a mix of climates. Low-growing ornamental grass that is fine for the state's east coast, may not do well on the west coast. North Florida is actually in three hardiness zones. The western part of the panhandle is mostly zone 8A. The center and the Gulf Coast of the panhandle is in zone 8B, when the temperatures are a little warmer. The east coast of north Florida is in zone 9A, where the temperatures are still warmer. So a plant that does well in the East may die out in the West.
Ornamental grass grows differently from regular grass. Instead of growing as separate blades of grass, it grows either in clumps or as running grass--when the plant sends out runners from underground rhizomes to form new plants. Clumping plants can be planted with other perennials. Running grass types should be planted by themselves as they can overrun other plants. Ornamental grass also produces flowers that grow on stalks higher than the grass itself.
Oriental fountain grass (pennisetum orientale) usually does not grow over 12 inches tall. It produces a dense, cascading foliage and it will expand sideways, producing more clumps of grass. The flowers look like pink or white fluffy plumes, grow to from 1-2 feet above the grass and last through the summer and fall. Quaking grass (briza media) grows to from 12 to 18 inches, tall and produces small heart-shaped flowers that turn from green to gold.
Oriental fountain grass is hardy in zones 6 to 10 (the latter all the way to the south of Florida). Quaking grass is hardy in zones 4-8, as far south as the Panhandle and central northern Florida.
Oriental fountain grass needs full sun, except in the hotter climates where it should get partial shade. Oriental fountain grass needs moist, well-drained soil. Quaking grass does well in any soil type, prefers partial to full sun and moist but not wet soil. It is also drought-tolerant.
Oriental fountain grass can be grown as a specimen plant, mixed with other perennial plants in a border or as a container plant. Quaking grass should be planted 1 foot apart as an individual specimen plant. Planted closer together, it becomes a ground cover.