Botanical Name: DASYLIRION LONGISSIMUM
Plant Common Name: Smooth Desert Spoon, Smooth Sotol, Dasylirion quadrangularis
Mexican Grass Tree, Toothless Desert Spoon, Toothless Sotol, Beargrass, Stick Palm, Grass Tree, Bear Grass, Junquillo
Origin and Habitat: Mexico and southern Arizona
General Description: The fine wiry leaves of this incredible desert plant create such a sculptural look they are coveted by modern landscape designers. Its dense rosette of foliage is stemless but very mature specimens develop a stout trunk-like base, though this is rarely seen in cultivated landscapes.
The Dasylirion Longissimum is a slow growing durable evergreen shrub. Small plants are relatively inexpensive, but larger ones are a fortune because they usually don’t grow more than one centimetre per year in their country of origin.
These make great specimen plants for xeriscape gardens and blend well in either tropical or arid gardens.
These make excellent potted specimens, and their symmetrical form provides a striking focal point, and display wonderful shadows when illuminated by night lighting.
This plant has a hemispherical form and unique long sculptural leaves making it perfect for focal point specimen plantings and large containers.
It is also great in xeriscapes and large succulent and cactus gardens. Very pretty when lighted from below. Dasylirion longissimum is fire-resistant and unloved by deer and rodents.
Trunk: Solitary, large, woody, felted with old leaves, 90-200 (or more) cm tall, but occasionally old plants may develop multiple heads of leaves, typically branching after flowering.
Over many years, it forms a trunk and can reach 10-15 feet tall.
Exposure: They thrive best in full sun, but can be grown with some shade and humidity, but may become leggy. Like most arid species, Dasylirion Longissimum needs full sun and very well drained soil. It is extremely heat tolerant.
Hardiness: Best where winter temperatures stay above 10° C, but can take some periods of frost.
(cold hardy up to -15 ° C). Plants in containers can be moved inside during longer cold spells.
Hardiness Zone: 8b-10b
Soil: Plant in very fast draining soil. It is adapted to a hot, dry environment, but has some tolerance to moisture and humidity when planted in a very well-draining soil.
Waterings: Provide little or no water in winter. Treat like a succulent. However, they grow faster if watered well (don't water the crown, though they rot easily or can cause fungal rots). In the garden they should be placed in a sunny, well-drained area with additional summer water in dry climates.
Fertilization: Most cacti and succulents can go long periods with little or no fertilizer
Use a good-quality cactus fertilizer, or fertilizer with low nitrogen content, according to directions. Lightly scatter fertilizer around the base of plants. If using liquid plant food, use at or less than recommended strength; NEVER over-fertilize Dasylirions.
Maintenance: Trim older dead leaves to reveal trunk if desired.
Blooming season: They may go years without blooming, then send up the tall flower stalk in summer. The bloom looks a lot like a giant torch or poker. The flower stem becomes woody with age and the flowers are replaced by dry brown fruits. These can be left to add architectural beauty to the landscape or cut and used in dry arrangements. Bloom time late winter/early spring.
Problems: Root and fungal rots in poor draining, wet soils.
Special notes: The leaves are flexible, unpinned and create movement in even the slightest breeze. These plants are dioecious, and require both male and female plants to set seed. Flowering occurs in winter.