Horticulture Unlimited Inc.

Plant Guide

‘Sticks of Fire’
‘Sticks of Fire’

Euphorbia tirucalli

This endangered species is recognized for its light green, pencil-thin, bush-like branches with miniature leaflets. It is fast-growing reaching heights of eight to ten feet or more in the southwest desert. In its native…

African or Tiger Aloe
African or Tiger Aloe

Aloe maculata

This fast, low-growing aloe produces short, stem-less rosettes and many offshoots that grow in low clumps. This plant will grow rapidly to twelve inches or more, producing many offsets over its lifetime. It has thick, su…

Agave cornelius
Agave cornelius

Agave americana ‘Cornelius’

The agave cornelius is a low growing, colorful plant. It has thick, wavy blue green and yellow variegated foliage with wide leaves. This spectacular plant has sharp black teeth along its leaves and a sharp tip. It will g…

Algerian Ivy
Algerian Ivy

Hedera canariensis

This fast-growing evergreen has thick, shiny, deep green, lobed leaves with reddish stems. New growth is a light green color. It rarely produces flowers, but if it does, they are whitish green in color. Algerian ivy can…

Argentine Mesquite Tree
Argentine Mesquite Tree

Prosopis alba

Native to South America, the Argentine mesquite is a beautiful tree with darker bark and a more vigorous growth rate than many other mesquite trees. Here in Southern Arizona, it grows to 40 feet high with a spread of 60…

Argentine Toothpick Cactus
Argentine Toothpick Cactus

Stetsonia coryne

The distinctive, night-blooming cactus grows thirty feet tall and ten to fifteen feet wide. Its columnar, grayish-green stems are approximately four inches in diameter with toothpick-like, grayish-white spines, protrudin…

Arizona Ash
Arizona Ash

Fraxinus velutina

This fast-growing, deciduous tree reaches thirty to forty-five feet and spreads twenty-five to forty-five feet or more, depending on conditions. It produces dark green, three- to six-inch-long leaves that are divided int…

Artichoke Agave
Artichoke Agave

Agave parryi v. truncata

Artichoke agave resembles an artichoke, as its common name implies. This slow-growing, clumping agave is native to southern Chihuahua and northern Durango in Mexico. It has short blue-gray leaves and grows two to three f…

Asparagus Fern
Asparagus Fern

Asparagus densiflorus ‘Sprengeri’

Asparagus fern is a mounding, spreading, evergreen that grows one to two feet with a three-foot spread. It is a fast-growing plant with bright green to yellow green, airy, fernlike, delicate leaves, and tiny thorns. It’s…

Autumn Sage
Autumn Sage

Salvia greggii

Autumn Sage is native to Western Texas and parts of New Mexico and Southern Arizona. It is a small, evergreen shrub that grows to about 3 feet tall and wide. Its small, dark green leaves have a slightly sticky coating. S…

Baby Sun Rose
Baby Sun Rose

Aptenia cordifolia

This sprawling plant forms a dense mat that grows in flat clumps along the ground from six to twelve inches tall. It has bright green, heart-shaped, succulent leaves and small, reddish-purple to pinkish-purple, button-li…

Baja Fairy Duster
Baja Fairy Duster

Calliandra californica

Baja Fairy Duster is a medium sized shrub that grows to 5 feet high and 5 feet wide. Medium green, twice divided leaves are one inch long and give this native of Baja California its tropical appearance. Scarlet red to re…

Banana Yucca
Banana Yucca

Yucca baccata

This yucca was named for its edible, banana-shaped fruit that was a historic food source for Native Americans. The plant grows slowly to three to five feet tall and wide with large, strap-like, dark-green foliage that is…

Beaked Yucca
Beaked Yucca

Yucca rostrata

The spectacular bloomer grows ten to fifteen feet tall, forming an attractive, thatched trunk and branching towards the top of the plant as it matures. It has narrow, slightly waxy, greenish-blue leaves with a thin, yell…

Bear Grass
Bear Grass

Nolina microcarpa

The evergreen accent plant is a great choice for desert and transitional gardens, forming a bold, grassy clump to about five feet tall and seven feet wide. The ends of its leathery, coarse, green leaves will fray to form…

Bear’s Breech
Bear’s Breech

Acanthus Mollis

The lush, herbaceous evergreen grows six feet tall and three feet wide with deep green, deeply lobed, shiny leaves, a clumping growth form, and underground rhizomes that spread as the plant matures. Stunning flower spike…

Beavertail Cactus
Beavertail Cactus

Opuntia basilaris

This interesting, oval-shaped cactus grows two to three feet tall and four feet wide. It has short, greenish-purple segments resembling the tail of a beaver. Brown, wooly looking, bristly spines grow along its edges, whi…

Black-spine Agave
Black-spine Agave

Agave macroacantha

This small agave forms clumps of short, tight rosettes growing one to two feet tall and two to four feet wide. It has a short stem and forms offsets at the base of the plant. Its foliage is bluish-gray to powdery blue. T…

Blackfoot Daisy
Blackfoot Daisy

Melampodium leucanthum

This low-growing plant with aromatic, daisy-like flowers has a mounded appearance with narrow grayish-green foliage. It grows to about one foot tall and eighteen inches wide. Small, abundant, white, daisy-like flowers wi…

Blanket Flower
Blanket Flower

Gaillaridia x grandiflora

The perennial continuous-flowering, rounded plant grows two to three feet tall from a taproot and spreads by underground rhizomes. It produces striking flowers and linear, dark green leaves that are serrated with coarse,…