Chilopsis linearis, 'Variety AZT™'
'AZT™Dora's Desert Rose'
.jpg)
The 'AZT Dora's Desert Rose' was named for Dora Douglas who added beauty to wherever she lived by planting a rose garden. This 'Variety AZT' Desert Willow produces abundant blooms during the growing season against a canopy of narrow, weepy, deep green leaves making the tree a colorful and striking addition to the landscape. The qualities that set ‘AZT Dora's Desert Rose’ apart from seed selections are flowers with pink colored petals and few seed pods.
'AZT™ Desert Amethyst'
The 'AZT Desert Amethyst' produces abundant blooms during the growing season against a canopy of narrow, weepy, deep green leaves making the tree a colorful and striking addition to the landscape. The characteristics that make 'AZT Desert Amethyst' stand out are the solid-colored, dark lavender flowers combined with thinner, more upright leaves.
'AZT™ Bi-Color'
The 'AZT Bi-Color' produces abundant blooms during the growing season against a canopy of narrow, weepy, deep green leaves making the tree a colorful and striking addition to the landscape. The qualities that set ‘AZT Bi-Color’ apart from seed selections are flowers with burgundy-colored petals that contrast with a paler pink throat.
Arid Zone Trees makes selections from thousands of trees propagated from seed. Only individual trees having the most desirable physical qualities (branching habits, leaf color, leaf canopy, and flower color) and sound horticultural characteristics (rooting, cold hardiness and growth rate) are selected for further study. These trees are then cloned (vegetatively propagated) and planted at our nursery for evaluation. The best of these trees are placed in our cloning production and are designated Variety ‘AZT™’. Since no single selection of any desert tree species is best adapted to all landscape applications, we continually search for new additions to our Variety ‘AZT™’.
At first glance the name Desert Willow seems like a contradiction in terms. Desert Willow (Chilopsis linearis) is not a true willow. Many people have attributed the name to the long (2" to 5"), slender, glossy green leaves that typically grow towards the ground. The leaf canopy has a weeping, willow-like appearance. Much of the literature refers to Chilopsis as a large shrub to small tree growing to 15' to 30' tall with spreads of 10' to 15'. In landscape settings, where trees are regularly watered and fertilized, Chilopsis grow to the stature of most other desert trees.
When incorporating Desert Willows into landscape designs architects should consider them medium sized mature trees that will occupy considerable space in the landscape. Chilopsis is an excellent accent tree when used in desert designs. Trees produce filtered shade that does not inhibit flowering of understory plantings. Young trees require regular pruning to develop and encourage graceful single or multi-trunked specimens. Without pruning, trees can look shaggy with thick leaf canopies and branches extending to the ground. Trunks are a slightly roughened gray- white and contrast nicely with the bright foliage and flowers.
Desert Willows are found in all the deserts of the southwest US and northern Mexico. Trees are found from 1500' to 5000' elevations, usually along streams or basins where rainfall collects. Trees are drought and winter deciduous, generally drop leaves in late November, and hardy to 10 degrees F. In summer months, young trees can be irrigated every other week. For optimal growth and flowering, mature trees should be deep watered every 2 to 4 weeks depending on soil profile. In the landscape, Desert Willows grow best in well drained soils and full sun exposures.
Chilopsis is one of the few desert tree species that produces flowers throughout the summer months. Trees produce beautiful, slightly fragrant, orchid-shaped flowers from early spring to fall. Chilopsis flowers also attract and provide nectar for hummingbirds. For many years growers and Universities have been selecting and breeding Chilopsis varieties for larger, brighter colored flowers. Depending on the variety, flower color varies from off-white to dark lavender. Flowers mature to produce 6" to 8" tan pods that spilt open to release seeds. Pods often do not drop from the tree and can be unsightly, particularly when trees are dormant. Pods can be pruned off during winter months.
Seed pods and cast flowers can be a litter problem in some settings. Desert Willows are well adapted to both lawn and traditional desert landscape settings. They are used as summer color accent trees, individual specimens, as screen plantings (usually left unpruned) or in groupings. Chilopsis bring summer color, cold hardiness and a unique lush look to arid landscape designs.
CULTURAL PRACTICES AND MAINTENANCE
Foster the development of a more dispersed root system and reduce the risk of wind throw by arranging irrigation emitters at varying distances from the trunk to encourage roots to "seek out" water and nutrients. Irrigation emitter arrangement along with other information on irrigations practices for desert trees can be found at www.aridzonetrees.com and click on the FAQ link.
Prune as needed to reinforce the structure and form of the tree. Periodic thinning is the most desirable method of pruning. Avoid hedging or heading back desert species, as this will only stimulate excessive branching. Do not remove more than 30% of the canopy during the summer as this can lead to sunburn injuries that can later be invaded by wood boring insects. Always use clean, sharp tools that are cleaned regularly in a 10% solution of bleach. For detail pruning guide see www.aridzonetrees.com and click on the FAQ interactive button.
Periodically insect pests can be a problem on some desert trees. On young trees, insect infestation can slow typical seasonal growth. Inspect trees during the growing season for common garden sucking insects such as aphids, thrip, whiteflies or psyllids. During dry months, (May and June) in dusty conditions, spider mites can appear. Monitor for infestation and apply controls as needed. Spray applications of water or water and Safer Soap give short-term control (3 to 7 days) for small insect population. For heavy infestation or longer control use federally registered insecticides. A contact insecticide application will kill existing adults. An application with a systemic soil drench will provide 8 to 12 weeks control for any post application insect hatchings or migration of insects. Before using pesticide for the first time or on new plants or cultivar, treat a few plants and check for phytotoxicty. Always read label and follow label instruction before using pesticides. For pesticide control recommendations contact a licensed pest control advisor.