Agave spp.: Agave, Century Plant

This document is a part of a series originally written by Edward F. Gilman.

Introduction

Agave is a genus which contains over 200 species of plants native to Mexico and desert regions of the southwestern United States. There is a high level of diversity among this species, from growth form, color, and size. Various species will have different uses in the landscape. Numerous cultivars are also available in the horticultural industry.

Agave is a succulent herbaceous perennial with a height of up to 10 feet and a spread of up to 15 feet (Figures 1 and 2). The thick evergreen leaves grow in a tight rosette and may have spines along the margins and tip of the leaf (Figure 3). Most Agave species are monocarpic, with each rosette producing one flower spike before the plant senesces; however, the plant generally produces offshoots or pups, which will continue to grow after the primary plant dies. Some Agave species can flower multiple times throughout their lifespan. The flower spike that is produced is an upright inflorescence which can reach up to 20 feet, depending on species (Figure 4). Although it is a common belief that Agave, also called century plants, only flower after 100 years, it generally takes between 15 to 60 years depending on the species. These tubular flowers are highly attractive to pollinators and hummingbirds (Figure 5). Various Agave species are suited for different uses in the landscape depending on their size and growth habit. Some uses include in containers and above-ground planters, or as specimen, accent, or rock garden plants.

General Information

Scientific name: Agave spp.

Pronunciation: uh-GAV-vay species

Common name(s): Agave; century plant

Family: Asparagaceae

Plant type: shrub

USDA hardiness zones: 9A through 11A; some variation depending upon species selection (Figures 6 and 7)

Planting month for zone 9: year-round

Planting month for zones 10 and 11: year-round

Origin: certain species native to North America (Agave decipiens, Agave virginica)

Invasive potential: certain species may be invasive; visit IFAS Assessment for more information (https://assessment.ifas.ufl.edu/)

Uses: border; accent; specimen; mass planting; container or above-ground planter; attracts pollinators; attracts hummingbirds

Availability: somewhat available, may have to go out of the region to find the plant

Description

Height: 2 to 10 feet; dependent upon species selection

Spread: 3 to 15 feet; dependent upon species selection

Plant habit: round

Plant density: open

Growth rate: slow

Texture: coarse

Foliage

Leaf arrangement: alternate

Leaf type: simple

Leaf margin: serrated; some species lack spines

Leaf shape: lanceolate

Leaf venation: none, or difficult to see

Leaf type and persistence: evergreen

Leaf blade length: less than 1 foot to 8 feet; dependent upon species

Leaf color: green; blue; yellow; white; variegated; dependent upon species

Fall color: no fall color change

Fall characteristic: not showy

Flower

Flower color: white; pale yellow

Flower characteristic: flower stalk may be produced at almost any point during the year; each rosette is generally monocarpic, blooming only once

Fruit

Fruit shape: oval

Fruit length: 1 to 3 inches

Fruit cover: dry or hard

Fruit color: brown

Fruit characteristic: persists on the plant

Trunk and Branches

Trunk/bark/branches: not particularly showy; usually with one stem/trunk

Current year stem/twig color: not applicable

Current year stem/twig thickness: not applicable

Culture

Light requirement: plant grows in full sun, plant grows in partial shade

Soil tolerances: alkaline; acidic; clay; sand; loam

Drought tolerance: high

Soil salt tolerance: moderate

Plant spacing: 36 to 60 inches

Other

Roots: usually not a problem

Winter interest: no special winter interest

Pest resistance: no serious pests are normally seen on the plant

Toxicity: some species exhibit low toxic characteristics; sap from leaves may cause dermatitis; toxic component includes calcium oxalate crystals

Use and Management

Agave are extremely hardy plants, with a high level of drought tolerance, and many species being salt tolerant. This plant thrives when planted in a full sun location on well-drained sandy soil. Some species will also tolerate partial shade. This plant requires little irrigation and maintenance once it is established. Many species of Agave have serrated leaf margins and terminate at a sharp point. Care should be taken with locating this plant in the landscape. The sharp tips at the end of the leaf may be removed to protect children and pets. Certain Agave varieties have smooth leaf margins and are a suitable option to decrease the risk of injury from these plants.

Various Agave species may be used in different ways depending on the size of the plant and landscape. Larger commercial landscapes may have room for larger Agave species or mass plantings. Smaller Agave species are well-suited for containers or above-ground planters. These plants may also be used as borders or in a rock garden.

Propagation is by detaching the well-rooted suckers appearing at the base, or by uprooting germinating seedlings near the plant.

Design Considerations

The bold form and coarse texture of Agave make it perfect as a specimen plant in highly visible spaces in the landscape. Use with companion plants that are softer, with small foliage and mounding or spreading forms to contrast and highlight the stiff, upright form of the leaves. Pairing with plants that have more texture in the foliage will also contrast with the smooth, stiff leaves. To highlight the soft bluish-green in the leaves, use plants with dark green foliage or plants with small to medium flowers with cool, bright colors, such as purples, blues, and deep corals. Another option is to complement the soft green with soft yellow or white wispy grasses. Large masses of low-growing companion plants around the base or in front of the century plant will create a nice setting to show off the form.

Pests and Diseases

Pests include Agave snout weevil. No diseases of major concern.