Sometimes things that are old become new again. A case in point is the Chaste Tree also sometimes called Monk's Pepper, Vitex agnus-castus. If you travel through the older residential sections of metropolitan Phoenix it is not uncommon to find mature Vitex trees 20 to 25' tall. These trees are valued for the dense shade they provide and the spectacular displays of large cone shaped clusters of purple flowers.

Chaste trees are found distributed throughout the tropical and subtropical regions of the eastern and western hemisphere. They are thought to have originated in the Mediterranean where it grows along streams or in areas with readily available water. Trees grow at a moderate rate to a height and spread of 15' to 25'. This optimal growth is seen in warmer climates where supplemental irrigation and fertilization are applied. In colder regions the growth rate slows and the mature stature is smaller.

Vitex can be used in landscapes as a shrub or hedge planting where it is heavily pruned or sheared to increase flower production. Vitex will tolerate being planted in both turf and non-turf areas. Dense shade is produced by a broad canopy of dark green leaves that are themselves made up of 3 to 5 narrow, pointed leaflets. The tree is fully deciduous in winter and cold hardy to 0 degrees F. Upright, V-shaped multiple trunked specimens are more common than standard or single trunked forms.

Starting in late spring and continuing through early summer (and occasionally in early fall) Vitex produces showy, cone-shaped clusters of flowers. These "spikes" of flowers can be 5" to 7" long and vary in color from dark purple to white. Purple is the most desirable and widely used flower color. Round dark brown to black, "pepper corn like" seed develop from these flowers. The seeds as well as shoots and leaflets are highly aromatic when crushed. The ability to provide dense shade combined with summer flowers and cold hardiness make Vitex an ideal tree for desert landscape designs anywhere in the arid southwest.

Celtis reticulata, Netleaf Hackberry or Canyon Hackberry is irregularly distributed over a range that extends from the Chihuahuan desert on the south to the arid plains of eastern Washington on the north. It is typically found in dry, rocky hillsides, canyons and dry stream beds from 2500' to 6500' above sea level. This tree has a rustic, drooping form with twisted branches and trunks, densely divided branches and heavily veined leaves.

Hackberries are member of the Elm family with bright green, lopsided, saw-toothed elm tree-like leaves. Leaf size may vary in response to environmental conditions with smaller leaves produced when trees are stressed for water or fertilizer. The trees provide fall color with turning bright yellow with the onset of persistent cold temperatures. Tiny nondescript flowers in spring mature into tiny red to orange berries in fall. Berries attract wildlife and birds in desert and urban settings.

Unwanted seedlings or volunteer plants are easily controlled with herbicides or a hoe. It can grow as either a large shrub or a medium sized trees. Some mature specimens can grow to 25 to 30' tall. The trees are well adapted to desert heat and are hardy to -20 degrees F. It grows best in well draining soils with supplemental summer irrigation. To a limited extent Celtis can be naturalized to desert conditions but will not survive extended droughts without irrigation. Trees should be pruned in winter to maintain an attractive shape and structure. The irregular, natural form of this tree makes it ideal for naturalistic desert landscapes or as a tree to soften the transition back to undisturbed desert. By providing food and shelter, Canyon Hackberry can be used to attract birds and wildlife into the landscape.