Tree
Fruitless Mulberry
Morus alba 'Fruitless' · Moraceae
Also called: White Mulberry (male/fruitless selection), Common Mulberry
Fruitless Mulberry (Morus alba 'Fruitless') is a moderate-water tree well suited to Tucson and the low desert. It thrives in full sun, with a fast growth rate. Expect greenish (catkins) blooms spring.
Fruitless Mulberry at a glance
- Water use
- Moderate (established)
- Sun
- Full sun
- Mature size
- 30-50 ft tall and 30-45 ft wide, forming a broad, dense, dome-shaped canopy.
- Growth rate
- Fast
- Bloom
- Greenish (catkins), Spring (inconspicuous; fruitless male clones set little or no fruit)
- Cold hardiness
- Fully cold-hardy in Tucson; deciduous and tolerates hard freezes well below 9a/9b lows. No frost protection needed.
- Soil
- Very adaptable; grows in most Tucson soils including alkaline clay, but does best with deep, well-drained soil and benefits from a large irrigated root zone.
- Native range
- Native species (Morus alba) from China; cultivated fruitless male clones
- Best used as
- Fast shade tree, Lawn/large-yard shade, Quick canopy for new landscapes
- Wildlife
- Foliage and (on fruiting types) berries feed birds; fruitless clones offer mainly cover and shade.
- Toxicity
- Foliage and unripe parts contain latex/sap that can be mildly irritating; not considered seriously toxic to pets or children. Pollen from male fruitless clones is a significant allergen.
How to grow Fruitless Mulberry in Tucson & the low desert
Watering
Has higher water needs than true desert trees; water deeply to 2-3 ft to support its large canopy. In summer, deep soakings every 7-14 days; stretch intervals in spring/fall and water about monthly in winter. Inadequate water causes leaf scorch and limb dieback.
Fertilizer & nutrients
Benefits from a spring application of a balanced or nitrogen fertilizer to fuel its fast growth and dense foliage; supplement with chelated iron if alkaline-soil chlorosis (yellowing leaves) appears.
Pruning & care
Prune hard while dormant in winter to control its large size, remove deadwood, and maintain strong scaffold branches; it tolerates heavy pruning and pollarding. Establish good structure early to prevent weak, included-bark crotches that split in monsoon winds.
Notes
A fast, dense shade tree but with real drawbacks in Tucson: male fruitless clones are heavy pollen producers and their sale/planting is restricted in some Arizona jurisdictions (notably Pima County and Maricopa County) due to allergy ordinances—verify local rules before planting. Thirsty, aggressive surface roots, and high litter; site away from foundations, sewer lines, and pavement. Provide ample water and space.
Sources: University of Arizona Cooperative Extension; Pima County / City of Tucson pollen-control ordinances; AMWUA Landscape Plants for the Arizona Desert