Doodia media, also known as rasp fern (or pukupuku in Māori), is a fern species in the family Blechnaceae. The species was formally described by botanist Robert Brown in 1810. Distribution of the species includes New Zealand's North Island and the upper part of the South Island (Nelson and Marlborough). It is also found in Australia and Lord Howe Island.
Young fronds contain flavonoids that protect them from ultraviolet radiation and give them a pink colour.Phylogenic studies have shown that the genus Doodia is embedded within the paraphyletic genus Blechnum, when that genus is broadly circumscribed. Christenhusz et al., 2011, therefore reassigned all Doodia species to Blechnum. Doodia media R.Br. was transferred to Blechnum medium and Doodia media subsp. australis (Doodia australis) was transferred to Blechnum parrisii. Other sources, such as World Ferns, based on the Pteridophyte Phylogeny Group classification, split Blechnum, accepting Doodia.
Common rasp fern generally has good resistance to disease and is affected by relatively few insect pests. Its care is regarded as difficult, because it requires a moist environment and frequent watering. However, the roots are vulnerable to rot if overwatered and if the environment is not well ventilated. Common rasp fern is suitable for people with some growing experience, and most people can keep it alive for a certain period. However, it may struggle to thrive, and its leaves can dry out and become less healthy over time.
How to keep Blechnum Medium.
Light
The common rasp fern comes from habitats such as forest understories or rocky areas that provide natural shade. It prefers full shade but can tolerate partial sun.
Temperature
Common rasp fern does best in forest thickets. It is very sensitive to temperature and humidity; excessive heat, dry conditions, or strong sunlight can all make the plant uncomfortable. In summer it needs adequate shading and a high-humidity environment. Generally it does not require special care in winter, but an extended winter drought can still be fatal.
Botanical profile.
- Plant Type
- Fern
- Life Cycle
- Perennial
- Genus
- Blechnum
- Family
- Aspleniaceae
- Hardiness Zone
- 8-11
- Mature Height
- 34 cm
- Mature Spread
- 40 cm
- Leaf Color
- Dark Green, Olive Drab
- Leaf Type
- Evergreen
- Planting Time
- Spring, Summer, Autumn
- Native Area
- Fiji
