Icarus is a genus of ferns in the family Blechnaceae, subfamily Blechnoideae, with a single species Icarus filiformis, according to the Pteridophyte Phylogeny Group classification of 2016 (PPG I). The genus is accepted in a 2016 classification of the family Blechnaceae, but other sources sink it into a very broadly defined Blechnum, equivalent to the whole of the PPG I subfamily. Icarus filiformis, synonym Blechnum filiforme, is known as thread fern or pānoko in Māori. It is endemic to New Zealand. It has a creeping and climbing habit. It has three different types of fronds: long climbing fronds with long pointed leaves, shorter creeping fronds with nearly round leaves, and fertile fronds with threadlike leaves that give the species its common name.
Thread fern has strong resistance to disease and is generally not susceptible to illnesses. However, it can be vulnerable to pests and diseases present in its environment. Such infections are typically mild. Regarding care, this plant needs moderate maintenance. It requires regular pruning to preserve a tidy appearance and support healthy growth. Applying fertilizer can also encourage flowering. The thread fern is appropriate for anyone with outdoor space, such as a garden or patio, and does not demand extensive care experience. It may need additional attention when grown indoors.
How to keep Blechnum Filiforme.
Light
Thread fern is native to habitats like forest understories and rocky sites, where it grows in natural shade. It prefers partial sun but can tolerate full sun or deep shade, showing its adaptable, hardy character.
Temperature
The thread fern is native to tropical areas where the climate is generally warm and humid. Consequently, it is adapted to high temperatures and humidity. It does not tolerate abrupt temperature changes and prefers a steady thermal environment, so indoor temperature fluctuations should be avoided. It usually cannot withstand cold and needs warmer conditions to grow. If the ambient temperature falls too low, the plant may stop growing or even die.
Fertilizer
The thread fern needs the most fertilizer during its active growth phase, which occurs mainly in spring, summer, and early fall. Fertilizing supplies essential nutrients the soil may lack, encouraging healthy root and stem growth and supporting the attractive foliage that is a key trait of this plant.
Botanical profile.
- Plant Type
- Herb
- Life Cycle
- Perennial
- Genus
- Blechnum
- Family
- Aspleniaceae
- Hardiness Zone
- 9-11
- Mature Height
- 30 cm to 61 cm
- Mature Spread
- 20 cm to 30 cm
- Leaf Color
- Green, Blue
- Leaf Type
- Semi-evergreen
- Flower Size
- 1.02 cm to 2.03 cm
- Planting Time
- Spring, Summer
- Native Area
- New Zealand
