Cactus, Agave & Yucca
Upright Cactus: Cactus that grows taller than it is wide, having arms either originating from the base or along the structural branches.
Barrel Cactus: Native, and many non native, plants with a variety of needles with usually vertical ribs, but sometimes swirled. Generally they grow as tall as they are wide, but mature specimens will usually be taller than wide. A variety of flower colors occur in the spring.
Agave: A few native and many non native agaves are grown in Tucson. Agaves can range in size from 6" tall and wide to 8' tall and wide. They generally grow as tall as they are wide. Fleshy sword-like fronds emanate from central rosette. Straight or curled spines may be along the edge of the fronds. A soft or sharp spine may be at the end of the frond. They can be grey, grey-green, green or variegated with white and yellow hues. The vast majority of agaves die after they have their one and only bloom, some with-in 10 years, most after many decades.
Yucca: A succulent plant that grows from a rosette similar to an agave but has no thorns on the leaf sides. Yuccas flower ever year growing a spear with an off white bell shaped flower unlike agaves that flower once in a life time then die. All varieties of yucca branch and with enough time produce trunks.
Prickly Pear: A succulent plant that grows pads with thorn patterns varying from 1/16 of an inch to 3 or more inches. There are a few prickley pears that have no thorns. Height and width are specific to each variety some can get very large so make sure to check. Prickley Pear are easily propagated by just removing a pad and replanting.
Aloe: Native to South Africa aloes, many thrive in Tucson. They have the fleshy sword like fronds similar to agaves, but aloes are softer with nowhere near the spines of agaves. After a period of time aloes form trunks and reach heights of 6' to 10'. Some aloes have multiple trunks, they bloom in the winter and early spring, their flowers can be quite spectacular. Be careful of sun exposure and cold tolerances of some aloes.
Accent Plants: Any plant used in a landscape that is posed or given accommodations to draw the eye.