It is considered a fast growing tree, and is the case with many fast-growing trees, it is relatively short-lived (more info). This link to arborday.org defines growth rate of trees in terms of inches per year, and it describes fast growth as 25” per year or greater.

Foliage of Desert-Willow. the summer if rainfall is sparse. The blooms occur at the tips of the branches and on new growth. The extremely fragrant, orchid-like blooms are most often seen in shades of lavender and pink but a white variety is occasionally found.

Sow the seeds no deeper than ¼ inch (6 mm.) deep in flats or nursery pots. Keep the soil relatively moist and within one to three weeks, desert willow seed germination will take place. When seedlings produce two sets of leaves, or are at least 4 inches (10 cm.)

By nature it's a multi-trunked tree but can be pruned into a single trunk specimen or grown as a small shrub. Because it lacks thorns and the roots are not invasive, it can be planted close to walls and paving without causing structural problems.. . . . .364011234167!]0000000000000009783314147432!]