Diastella

Description

Diastella is a small genus of flowering plants in the family Malvaceae, native to the Hawaiian Islands. The genus comprises only two known species, Diastella kauaiensis and Diastella waialealae, both of which are highly endangered and considered critically endangered by the International Union for Conservation of Nature (IUCN).

Taxonomic Information

Appearance

Diastella plants are small shrubs that grow up to 1.5 meters tall. They have leathery, dark green leaves and produce small, white, fragrant flowers that bloom in clusters. The flowers have five petals and a yellow center, and they are surrounded by a prominent calyx with five sepals. The fruit is a dry, woody capsule that splits open to release many small, black seeds.

Care Guide

Diastella plants are difficult to cultivate and require specific growing conditions to thrive. Here are some tips to care for your Diastella plant:

• Water: Water your Diastella plant regularly, but make sure the soil is well-drained and never soggy.
• Fertilization: Use a balanced fertilizer every two weeks during the growing season.
• Soil: Use a well-draining soil mix that is rich in organic matter.
• Sunlight: Diastella plants prefer bright, indirect light or partial shade.
• Hardiness Zones: Diastella plants are only hardy in USDA zones 10 and 11.

Common Pests & Diseases

Diastella plants are susceptible to several pests and diseases, including:

• Spider mites: These tiny pests can infest the leaves and cause yellowing and webbing.
• Scale insects: These pests feed on the sap of the plant and can cause wilting and yellowing of the leaves.
• Fungal diseases: Diastella plants are prone to fungal diseases such as powdery mildew and root rot.

Habitat

Diastella plants are endemic to the Hawaiian Islands and are found in dry, rocky areas at elevations of 300 to 1,200 meters. They grow in the understory of dry forests and shrublands, and they are often found on steep slopes and cliffs.

Question and Answer

Q: Why are Diastella plants endangered?
A: Diastella plants are highly endangered due to habitat loss, invasive species, and overcollection for horticultural trade.

Q: Can Diastella plants be grown indoors?
A: It is possible to grow Diastella plants indoors, but they require bright, indirect light and specific growing conditions to thrive.

Q: What is the difference between Diastella kauaiensis and Diastella waialealae?
A: Diastella kauaiensis is a larger plant with larger flowers, while Diastella waialealae is smaller with smaller flowers. They also have different distributions, with Diastella kauaiensis found on Kauai and Diastella waialealae found on Oahu.

Q: Can Diastella plants be propagated?
A: Diastella plants can be propagated from cuttings or by seed, but they are difficult to propagate and require specific growing conditions.

Related Plants

• Abutilon
• Hibiscus
• Malva
• Sida

References

• Wagner, W.L., Herbst, D.R., & Sohmer, S.H. (1999). Manual of the Flowering Plants of Hawai’i. University of Hawaii Press.
• International Union for Conservation of Nature. (2021). Diastella kauaiensis. The IUCN Red List of Threatened Species 2021: e.T15178A3135412. https://dx.doi.org/10.2305/IUCN.UK.2021-1.RLTS.T15178A3135412.en
• International Union for Conservation of Nature. (2021). Diastella waialealae. The IUCN Red List of Threatened Species 2021: e.T15179A3135436. https://dx.doi.org/10.2305/IUCN.UK.2021-1.RLTS.T15179A3135436.en