Century plant (Agave schidigera 'Shira-ito-no-ohi')

Overview

The Agave schidigera ‘Shira-ito-no-ohi’ is a highly desirable succulent prized for its dense, elegant rosette form and unique textural detail. As a variegated cultivar, it displays dark green leaves bordered by fine, creamy white margins and spectacular, curly white marginal filaments that give it its Japanese common name meaning “queen of white thread.” This slow-growing Century plant lends a strong architectural presence to xeriscapes or container gardens.

Though slow to mature, this perennial succulent ultimately forms a substantial basal rosette, often reaching up to 1 foot tall and 2 feet wide. While its common name suggests a century of life before flowering, the Century plant typically blooms outdoors between its 10th and 25th year before dying, making the rare flowering event quite spectacular.

Cultivating Agave schidigera ‘Shira-ito-no-ohi’ offers gardeners a low-maintenance focal point suitable for dry, sunny locations. Its sharp features and robust nature make it an excellent choice for contemporary or desert-themed plantings where excellent drainage is guaranteed.

Fast Facts

• Plant Family: Asparagaceae
• Plant Type: Herbaceous perennial
• Hardiness Zones: USDA Zones 8-10
• Size at Maturity:
  • Height: 0.5-1 ft
  • Spread: 1-2 ft
• Bloom Time: Rarely flowers
• Bloom Description: Greenish-yellow
• Sun Exposure: Full sun to part shade
• Water Needs: Medium
• Maintenance Level: Medium

How to Grow

For optimal health, plant Agave schidigera ‘Shira-ito-no-ohi’ where it receives full sun, though it will tolerate light shade. The most critical factor in establishing this species is soil drainage; sandy or gritty mixes are ideal. Where winter hardy (Zones 8-10), best growth occurs when the medium retains some moisture but drains sharply.

Water needs are categorized as medium. While the Century plant tolerates drought once established, providing consistent moisture leads to superior growth. Crucially, avoid wet, poorly-drained soils at all costs, as soggy conditions are the primary cause of root rot in container or in-ground specimens.

This agave can be propagated using seeds or the suckers that occasionally form at the plant base. If growing indoors, use a standard cactus-type potting mix to ensure sufficient aeration and drainage to prevent moisture retention around its sensitive roots.

Landscape Uses

The architectural structure provided by Agave schidigera ‘Shira-ito-no-ohi’ makes it an outstanding focal point or tropical accent in hardy landscapes. It serves well as a small specimen plant, drawing the eye with the delicate, white, hair-like filaments contrasting against the rigid green foliage.

It is highly effective when planted in dedicated cactus or succulent garden areas, often paired with contrasting textures like fine grasses or large, smooth boulders. Because its needs center around dryness and sharp drainage, it integrates beautifully into rock gardens or retaining wall plantings where other plants struggle.

For gardeners extending its use beyond its hardiness range, the Century plant thrives as an impressive container plant. Grown indoors, it acts as a sophisticated architectural element in modern interiors, provided it receives bright light and is potted in a fast-draining medium.

Standout Features

Noteworthy Characteristics

Agave schidigera, commonly known as century plant, is a slow-growing, rosette-forming, perennial succulent native to Mexico’s rocky cliffs. Its rigid, lanceolate green leaves feature sharp tips and striking white marginal hair-like filaments, setting apart the ‘Shira-ito-no-ohi’ cultivar with its variegated creamy-white borders. Plants are monocarpic, eventually sending up a spectacular, stout, 10-foot flowering stalk, after which the main crown dies.

Tolerances

• Drought
• Shallow-Rocky Soil

Potential Problems

While generally robust, the Agave schidigera ‘Shira-ito-no-ohi’ is susceptible to poor drainage, which quickly leads to fatal root rot, especially when soils remain perpetually moist. Monitor for slugs and snails, which may chew on the succulent foliage, leaving unsightly damage. Globally, the agave weevil remains a significant pest threat in endemic regions and should be managed proactively if present in your area.

Frequently Asked Questions

What hardiness zones is Century plant suitable for?

The Agave schidigera ‘Shira-ito-no-ohi’ is winter hardy in USDA Zones 8 through 10.

How large does Agave schidigera ‘Shira-ito-no-ohi’ grow?

This cultivar reaches a mature height between 0.5 and 1 foot tall, with a spread of 1 to 2 feet wide.

What sun exposure does Century plant need?

This agave prefers full sun but demonstrates good tolerance for part shade conditions.

Conclusion

The Agave schidigera ‘Shira-ito-no-ohi’ brings unique texture and strong form to the modern garden with its delicate white filaments adorning stout leaves. This Century plant variety is low-maintenance, provided its singular, non-negotiable requirement—superior soil drainage—is met. Before planting, confirm your location falls within Zones 8-10 or plan for container culture.

Companion Planting

When designing arrangements for Agave schidigera ‘Shira-ito-no-ohi’, select companions that share its architectural presence and love for dry conditions. Pairing it with spreading sedums or low-growing blue fescue grasses provides a wonderful contrast in texture and color. In xeriscape beds, consider using decorative gravel or decomposed granite as mulch to further enhance drainage and highlight the rosette shape of this specific Agave schidigera cultivar.

Design Ideas for Focal Points

Because of its striking coloration and texture, the ‘Shira-ito-no-ohi’ variety functions best as an undeniable focal point rather than filling in a mass planting. Place it near entryways or at the corner of a patio where its beauty can be appreciated up close, particularly highlighting the marginal hairs. Grouping three of these agaves in a triangular formation over coarse gravel creates a minimalist, impactful statement that emphasizes the plant’s inherent nobility.