A beautiful clump of dioon at Miami's Fairchild Tropical Garden.
The fabulous virgin's palm has stiff, upright blue-green to gray-green leaves that resemble futuristic radio antennae. Technically the virgin's palm is not a palm but rather a cycad, belonging to a group of cone bearing plants which trace their origins back to the ancient flora of the early Mesozoic era. Virgin's palm grows to about 11 ft (3.4 m) tall under optimal conditions. The trunk may reach 4-12 in (10.2-30.5 cm) in diameter. Virgin's palm has 15-20 leaves that are featherlike (pinnate), about 6 ft (1.8 m) long, and extend radially out from the trunk. The 120-160 leaflets on each leaf are small, linear, leathery and taper to a sharp point. The edible seeds produced in female cones take more than a year to mature.
Virgin's palm grows in tropical deciduous oak forests, and in harsh, dry conditions in Mexico, Honduras and Nicaragua.
The long lived and slow growing virgin's palm prefers well drained, gritty soil with plenty of water, especially in dry weather. Virgin's palm will grow in soils with few nutrients, in limestone or serpentine soils, in sandy soil, and on extremely steep slopes. Naturally undemanding for nutrients, virgin's palm responds very well to regular applications of fertilizer. Growth can be greatly improved through the application of fertilizers. Most growers find that a fertilizer having an even NPK (Nitrogen, Phosphorus, Potassium) balance, and supplemental trace elements, provides a good start for cycads. Cycads may then be kept growing well with regular applications of a balanced slow release formulation such as Osmocoteº or Dynamiteº.
Light: Virgin's palm thrives and grows best in partial shade. Moisture: The virgin's palm prefers moist soil with good drainage for optimal growth. An established virgin's palm is considered drought resistant. Hardiness: USDA Zones 8 - 11. Mature and established plants have been reported to tolerate temperatures down to 9ºF (-12.8ºC) for four days. Dioon edule is one of the most cold hardy cycads. Propagation: Virgin's palm may be propagated by seeds or by division and replanting of the attractive offsets or "pups" formed at the base of the plant.
Virgin's palm can be used in many ways in a landscape. Try the Asian style, with large paired plants in containers or feature beds that flank driveways, doorways or gates. A single large specimen makes an excellent feature plant in a landscape that emulates a tropical or desert setting. Use dioon to substitute for a true palm where a large crown is desired, but without a tall trunk. A virgin's palm can be a spectacular accent in a small garden where space is limited. Virgin's palm also makes an impressive understory to a larger tree or structure that allows at least partial sunlight to filter through. Virgin's palm is a perfect addition to accent a xeric landscape.
Use virgin's palm for that special accent in your landscape. Virgin's palm is considered easy to grow and a good choice for low-maintenance landscapes. The genus name Dioon comes from the Greek, meaning "two egg", because the seeds are produced in pairs. The species name edule is derived from the Latin, meaning "edible." Young seeds of virgin's palm are ground and cooked into tortillas. The leaves (fronds) of virgin's palm are used for decoration, especially in religious ceremonies.
The giant dioon (Dioon spinulosum) is similar but larger in stature and less cold hardy.
The leaflets of virgin's palm taper to a sharp point. It is well advised to plant virgin's palm away from footpaths and walkways. Wear heavy gloves when handling or working close to the virgin's palm to avoid getting jabbed by the sharp points of the leaflets.