Desert penstemon

Sun

Full sun; light afternoon shade is useful in very hot desert gardens.

Water

Low once established. Water during establishment, then allow the soil to dry between occasional deep waterings.

Soil

Lean, sharply drained sandy, gravelly or rocky soil. Tolerates alkaline soil; struggles in wet clay and rich, moisture-retentive beds.

Height

2-3 ft (0.6-0.9 m)

Spread

1-2 ft (0.3-0.6 m)

Flowers

Rose-pink to magenta tubular flowers in spring and early summer; occasional repeat flowering after summer rain.

Foliage

Blue-green, broadly oval leaves with toothed edges; upper leaves clasp the flowering stems. Usually evergreen in mild climates, but may lose foliage in cold winters.

Growth

Moderate

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

   1 ft (0.3 m)

2. After 1 year

   1.5 ft (0.45 m)

3. After 2 years

   2 ft (0.6 m)

4. After 3 years

   2.5 ft (0.75 m)

   full size

About 3 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

Safe

Native to

the US

Growth rate

Moderate

• Plant with the crown at soil level in a sharply drained bed; use a raised mound where winter rainfall is high.
• Water new plants when the root zone dries, reducing frequency as roots establish.
• Give established plants occasional deep water during prolonged drought rather than frequent light irrigation.
• Avoid routine feeding and rich compost, which encourage weak growth.
• Use a light gravel mulch and keep it clear of the crown; avoid moisture-holding organic mulch.

Pruning. After the main flowering flush, cut spent stems back to healthy leafy growth, leaving a few if you want seed. In spring, remove dead or winter-damaged stems without cutting hard into bare woody bases.

Late winter

Check that water drains away from the crown and clear away wet leaf litter.

Spring

Remove dead growth and plant out in a sunny, sharply drained position once the soil is workable.

Late spring

Enjoy the main flowering display and mark a few stems to keep for seed.

Early summer

Trim finished flower stems back to leafy growth to tidy the plant and encourage possible repeat bloom.

Summer

Water deeply only when needed during extended drought, allowing the soil to dry between waterings.

Autumn

Collect dry seed capsules and sow outdoors in pots protected from excessive rain.

• Plant in small groups through a gravel garden for upright pink flowers above low, blue-green foliage.
• Combine with agaves, yuccas and small ornamental grasses in a dry border.
• Use on sunny slopes or raised beds where drainage is better than in surrounding ground.
• Place beside a patio or path where visiting hummingbirds can be watched in North American gardens.

Garden styles it suits: Desert modern, Southwestern, Desert / xeriscape, Dry gravel garden, Pollinator garden and Wildlife garden.

Plant it with: Desert marigold, Blackfoot daisy, Red yucca, Blue grama, Indian ricegrass and Banana yucca.

Wildlife: The tubular flowers attract hummingbirds within their native range and are also visited by bees. Leaving some flower stems to set seed supports natural reseeding.

• Root and crown rot in wet soil: improve drainage or move to a raised gravelly bed, and reduce irrigation.
• Floppy stems in shade or rich soil: provide more sun and stop feeding.
• Aphids on tender shoots: dislodge with a firm spray of water and preserve beneficial insects.
• Declining older plants: replace short-lived clumps with seedlings or cuttings rather than relying on heavy pruning.

Not known to be toxic to people, cats, dogs or horses. Species-specific safety information is limited, and no part should be treated as food.

• Showy penstemon (Penstemon spectabilis)

  Also has broad, toothed, clasping leaves, but its flowers are generally lavender to blue-purple rather than the predominantly rose-pink flowers of desert penstemon.

• Parry's penstemon (Penstemon parryi)

  Has pink flowers too, but its leaves are narrower and usually smooth-edged, giving the plant a finer, more open appearance.

• Firecracker penstemon (Penstemon eatonii)

  Usually has scarlet-red flowers and narrower, smooth-edged leaves, unlike the pink flowers and broad, toothed leaves of desert penstemon.

The epithet pseudospectabilis means 'false spectabilis', referring to its resemblance to showy penstemon, Penstemon spectabilis.

Propagation. Grow from seed sown outdoors in autumn; winter chilling can help germination, which may be uneven. Take non-flowering shoot cuttings in late spring or early summer and root them in a free-draining medium.

Accepted botanical name

Penstemon pseudospectabilis

In the US and Canada

Native in the lower 48 states.

Native range

Arizona, California, Mexico Northwest, New Mexico and Utah.

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