Plant of the Week

Last hour on the KSL Greenhouse show we talked about bamboo plants for our area. There are two plants that are called bamboo but are not botanically related to the bamboo plants. The first one is Arundo donax or giant reed grass. It looks like bamboo but the stems are neither as stiff nor as durable. This plant grows well in our area and is much more common than true bamboo. Hardiness Zones: 5 to 8 Height: 12 ft Spacing: 6 ft Type: herbaceous perennial Flowers: Brown then white Comments: The large grass has a coarse texture and so may be used as an accent plant. The flower heads are brown but become white and then persist into winter. They are sometimes used as material for dried arrangements. Full sun and a moist soil are the required for best growth. Propagation: Seed, or division in spring. Cultivars: 'Variegata' - Yellowish white stripes on the leaves. This plant is a vigorous, invasive plant that should be planted only if it can be carefully contained. Fallopia japonica--Japanese Knotweed formerly Polygonum japonicum (P. cuspidatum) Hardiness Zones: 4 to 8 Height: 8 ft Spread: 24 in Type: herbaceous perennial Flowers: White Comments: Japanese Knotweed may also be called False Bamboo. It is a massive, thicket forming plant that can become a tenacious, virtually indestructible weed. The fleecy, white flowers are produced in late summer. The plant is not suggested for the small landscape. Propagation: Seed or division. Cultivars: 'Compactum' (P. reynoutria) - A compact version only 3 feet tall that produces pink flowers. The leaves turn red in the fall. 'Glozam' (Glo-worm TM) - A cultivar of 'Compactum' or P. reynoutria that produces pink flowers from mid-summer until frost. 'Variegata' - Leaves green, white and pink. Larry A. Sagers Regional Horticulturist Utah State University Thanksgiving Point Office