Whale's tongue agave

Sun

Full sun; light afternoon shade is helpful in exceptionally hot desert climates.

Water

Low once established. Water young plants during prolonged dry spells; let the soil dry between waterings and keep winter watering minimal.

Soil

Sharply drained sandy, gritty or rocky soil. Use a raised bed or mound on heavy ground; avoid sites that collect winter water.

Height

3-5 ft (0.9-1.5 m), excluding the flower stalk

Spread

4-6 ft (1.2-1.8 m)

Flowers

Mature plants produce a branched stalk roughly 10-15 ft (3-4.6 m) tall with greenish-yellow flowers, usually in late spring or summer. Flowering may take decades, and the flowering rosette then dies.

Foliage

Evergreen. Broad, thick, cupped blue-grey to silvery-blue leaves with small marginal teeth and a dark, sharp terminal spine.

Growth

Slow to moderate, faster with warmth and occasional summer water.

Care needed

Low

• Pollinators
• Deer resistant
• Drought tolerant
• Heat tolerant
• Low allergen

Northern hemisphere months. In Australia, shift them by six.

Difficulty

Moderate

Toughness

Fairly tough

Pick your zone, country, light and whether you have pets.

1. Planting day

   0.8 ft (0.25 m)

2. After 1 year

   1.3 ft (0.41 m)

3. After 2 years

   1.9 ft (0.57 m)

4. After 3 years

   2.4 ft (0.73 m)

5. After 5 years

   3 ft (1 m)

About 6 years to full size.

From a typical nursery size, at an average rate for this kind of plant. A rule of thumb, not a forecast.

Cats and dogs

Mildly toxic: may upset a stomach

Growth rate

Moderate

• Plant with the crown above surrounding soil level in a freely draining bed.
• Water deeply during establishment, then allow the root zone to dry before watering again.
• Use gravel mulch rather than moisture-holding organic mulch against the crown.
• Feed sparingly; established plants in the ground usually need no fertilizer.
• In cold, wet climates, provide an open-sided rain shelter in winter or grow in a container moved under bright, frost-protected cover.
• Wear thick gloves and eye protection, and leave its full mature spread clear of paths and play areas.

Pruning. In spring, remove only fully dead or badly damaged lower leaves, cutting close to their bases without injuring the crown. Do not shear the rosette or shorten healthy leaves; use protective clothing when handling it.

Spring

Plant after severe frost risk has passed, giving roots a warm growing season to establish.

Spring

Remove dead lower leaves and check the crown for softness or trapped wet debris.

Summer

Water new plants during dry spells; water established plants only when the soil has dried thoroughly.

Early autumn

Reduce supplemental watering as temperatures fall and check that drainage outlets remain clear.

Late autumn

Move container plants under cover where winters are too cold or persistently wet.

Winter

Keep the crown dry and check sheltered plants occasionally for rot and pests.

• Use a single rosette as a focal point in a sunny gravel garden.
• Repeat widely spaced plants against a plain wall to emphasize their rounded, architectural shape.
• Combine with drought-tolerant grasses and low flowering perennials for contrasting textures.
• Grow in a large, frost-resistant container with drainage holes where winter shelter is needed.

Garden styles it suits: Architectural minimal, Desert modern, Modern Mediterranean, Dry gravel garden, Desert / xeriscape and Southwestern.

Plant it with: Red yucca, Lavender, Russian sage, Blue grama grass, Ice plant and Autumn sage.

Wildlife: Flowers can provide nectar and pollen for insects and, where present, nectar-feeding birds. The long interval before flowering means it is not a dependable annual food source.

• Root or crown rot: prevent standing water, keep mulch away from the crown and shelter from persistent winter rain; badly rotted plants usually cannot be saved.
• Agave snout weevil in regions where it occurs: watch for sudden collapse, loose central leaves or a foul smell; remove infested plants promptly and seek local advice on protecting nearby agaves.
• Cold damage: wet freezes can scar or kill leaves; provide dry winter protection and avoid planting at the edge of its hardiness range in exposed, poorly drained sites.
• Scale insects or mealybugs: inspect leaf bases, isolate affected container plants and treat accessible infestations with a product labelled for these pests on succulents.

Treat the leaves and sap as harmful to people, cats, dogs and horses. Agave sap can cause marked skin and eye irritation, and chewing may irritate the mouth and digestive tract; species-specific poisoning information is limited. Spines can cause serious puncture wounds. Do not eat it, and seek medical or veterinary advice after ingestion or eye exposure.

• Parry's agave (Agave parryi)

  Usually forms a smaller, tighter rosette with shorter leaves and often produces offsets; whale's tongue agave has broader, more open, deeply cupped leaves.

• Harvard agave (Agave havardiana)

  Typically has narrower, more upright leaves with more conspicuous marginal teeth; whale's tongue agave has broader, tongue-shaped leaves.

• Century plant (Agave americana)

  Usually has much longer, narrower, arching leaves and readily produces spreading offsets, unlike the generally solitary whale's tongue agave.

The epithet ovatifolia means ovate-leaved, while whale's tongue describes the broad, thick, tongue-shaped leaves.

Propagation. Usually grown from seed, sown in a warm, freely draining medium. It normally remains solitary, so offsets are not a dependable propagation method; any rare rooted offset can be separated in warm weather.

Accepted botanical name

Agave ovatifolia

Native range

Mexico Northeast.

Sources: GBIF (CC BY 4.0) and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.