Pleurothallis allenii L.O.Williams

Allen's Pleurothallis

Moderate careEpiphyteNon-toxic8–15 cm

Pleurothallis allenii is a miniature epiphytic orchid from the wet tropical forests of Honduras and central Panama (Coclé province), growing at 550–1000 m on shaded, moss-covered branches. It belongs to the subtribe Pleurothallidinae (family Orchidaceae) and produces a single narrowly elliptical, leathery dark-green leaf about 7.5 cm long on a thin upright stem, with flowers emerging at the junction of stem and leaf. The blooms — roughly 2 cm across, deep burgundy-red with a yellow picotee edge on the sepals — appear reliably in spring, summer, and fall, often twice per season; this makes it one of the more rewarding miniature pleurothallids for a warm-intermediate humid vivarium. It does best potted in fine-grade sphagnum or bark kept consistently moist inside a closed or semi-closed enclosure; it tolerates a wide temperature range but dislikes prolonged drought or temperatures above 29 °C.

Build a terrarium with this plant
Allen's Pleurothallis image

Photo by Orchi·CC BY-SA 3.0

Care

Prefers high humidity, low light, with 13–29 °C, and reaches 15 cm at maturity.

Light

Shade tolerant(preferred)Indirect light

Humidity

High (60–80%)(preferred)Very high (80%+)

Temperature

10°C25°C40°C
13°C – 29°C

Soil

Sphagnum mix(preferred)Orchid mix

Moisture

Moist(preferred)

Propagation

Divide clumps when repotting into fresh sphagnum or fine bark, ideally in spring as new growth begins. Each division should carry at least one rooted ramicaul and a healthy leaf. Pot into small 5–7 cm containers or remount on cork with a sphagnum backing; keep in a warm, very humid environment with gentle air movement until new roots establish. This species grows quickly once settled, and successful divisions typically show new growth within 4–6 weeks.

Native range

Native to Central America.

Appearance

Growth habit

UprightClumping

Leaf shape

LanceOval

Leaf texture

LeatheryGlossy

Frequently asked

Can Allen's Pleurothallis grow in a closed terrarium?

Yes. Allen's Pleurothallis prefers high (60–80%) humidity, which is what a closed terrarium provides, and tolerates shade-tolerant conditions.

Does Allen's Pleurothallis need drainage?

Allen's Pleurothallis prefers a moist substrate. Drainage is helpful but not critical; consistent moisture matters more.

What humidity does Allen's Pleurothallis need?

Allen's Pleurothallis does best in high (60–80%) humidity.

Is Allen's Pleurothallis pet-safe?

Allen's Pleurothallis is considered non-toxic to common household pets.

How tall does Allen's Pleurothallis grow?

Allen's Pleurothallis typically reaches 8–15 cm at maturity.

How do you propagate Allen's Pleurothallis?

Allen's Pleurothallis can be propagated by division.

References

  1. 1

    POWO (Kew) — Pleurothallis allenii L.O.Williams (accepted name, authority, published Ann. Missouri Bot. Gard. 27: 275 (1940); synonyms: Acronia allenii, Zosterophyllanthos allenii; native range Honduras and Panamá; epiphyte, wet tropical biome)

    https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:202352-2
  2. 2

    IOSPE (orchidspecies.com) — Pleurothallis allenii (distribution: Coclé province, central Panama at 550–1000 m; single coriaceous narrowly elliptical leaf; flower ~2 cm, deep red/purple petals edged yellow, red lip; warm-growing; blooms spring–summer–fall; common name Allen's Pleurothallis)

    https://www.orchidspecies.com/pleuralleni.htm
  3. 3

    OrchidWeb — Pleurothallis allenii (distribution Panama, elevation 1500–3000 ft; deep red ¾" flowers with yellow outer edges; easy to grow and flower; blooms twice per year spring and fall; NZ sphagnum substrate, water as moss approaches dryness; low-medium light)

    https://www.orchidweb.com/orchids/pleurothallidinae/species/pleurothallis-allenii
  4. 4

    J&L Orchids — Pleurothallis allenii product page (3" narrow dark-green leaf on 1" stem; dramatic deep burgundy flowers with yellow picotee; blooms at junction of stem and leaf; intermediate difficulty)

    https://jlorchids.com/pleurothallis-allenii/
  5. 5

    Glass Box Tropicals — Pleurothallis allenii (warm to cool growing; medium to high moisture; epiphytic; terrarium suitable)

    https://glassboxtropicals.com/pleurothallis-allenii/
  6. 6

    Seattle Orchid — Pleurothallis allenii (origin: Panama; shade growing; damp; cold to warm; potted or basket-mounted; terrarium category)

    https://www.seattleorchid.com/Pleurothallis-allenii-p/tspleu-allenii.htm
  7. 7

    Greg App — Allen's Pleurothallis care (USDA Hardiness Zones 10a–12b; not known to cause harm to humans or pets; sensitive to dry soil; frequent watering ~0.5 cups every 7 days)

    https://greg.app/plant-care/pleurothallis-allenii-allens-pleurothallis
  8. 8

    AOS — Pleurothallis genus (high humidity essential; medium light; grow in seedling-grade epiphyte mix or mounted; water regularly, roots must not dry out for extended periods; cool to warm depending on species)

    https://www.aos.org/orchids/orchids-a-to-z/letter-p/pleurothallis.aspx
  9. 9

    Orchid Care Tips — Pleurothallis genus (humidity minimum 70%; cool below 21 °C for most; 700–1500 fc; fine-grade bark or NZ sphagnum; mount on twigs/bark with sphagnum; hate to dry out)

    https://www.orchid-care-tips.com/pleurothallis.html
  10. 10

    ASPCA Toxic and Non-Toxic Plants — Orchidaceae (Phalaenopsis and Jewel Orchid confirmed non-toxic to cats, dogs, and horses; orchids family-wide considered non-toxic)

    https://www.aspca.org/pet-care/aspca-poison-control/toxic-and-non-toxic-plants/phalaenopsis-orchid