Delta Maidenhair Fern

Adiantum raddianum

Family: Pteridaceae
Genus: Adiantum (ad-ee-AN-tum) (Info)
Species: raddianum (rad-dee-AH-num) (Info)
Synonym:Adiantum cuneatum
Synonym:Adiantum decorum
Synonym:Adiantum amabile
Synonym:Adiantum boliviense
Synonym:Adiantum colpodes
View this plant in a garden


Tropicals and Tender Perennials


Foliage Color:

Unknown - Tell us

Bloom Characteristics:

Unknown - Tell us

Water Requirements:

Requires consistently moist soil; do not let dry out between waterings

Where to Grow:

This plant is suitable for growing indoors


12-18 in. (30-45 cm)

18-24 in. (45-60 cm)


18-24 in. (45-60 cm)


USDA Zone 9b: to -3.8 C (25 F)

USDA Zone 10a: to -1.1 C (30 F)

USDA Zone 10b: to 1.7 C (35 F)

USDA Zone 11: above 4.5 C (40 F)

Sun Exposure:

Light Shade


Unknown - Tell us

Bloom Color:


Bloom Time:



Grown for foliage


Other details:

Unknown - Tell us

Soil pH requirements:

Unknown - Tell us

Patent Information:


Propagation Methods:

By dividing the rootball

Seed Collecting:

N/A: plant does not set seed, flowers are sterile, or plants will not come true from seed


This plant has been said to grow in the following regions:

El Cerrito, California

Hayward, California

Merced, California

San Francisco, California

Ventress, Louisiana

Sparks, Nevada

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Gardeners' Notes:


On Feb 4, 2011, annlof from Camarillo, CA wrote:

Slugs love the newly-opened fronds. But this fern is so beautiful that I still have to grow it... I've had good results growing the ferns in pots with copper stripping under their rims. My plants have experienced temps down to about 40 degrees without any negative effects.


On Sep 18, 2008, BayAreaTropics from Hayward, CA wrote:

What's interesting about this cultivar is that it grows true from spore. My orginal plant died a decade ago and still spore sprout on lava rock leaning into my fish pond in shady areas. And so do a few other Adiantum species self sow. It could be called "Bonsai Maidenhair" as it is a very delicate looking miniature of the normal A.raddianum. Large ones are striking floating clouds of fronds.


On Feb 17, 2007, Cretaceous from El Sobrante, CA (Zone 9b) wrote:

This fern has done well on our front porch, where it is shaded from the sun and protected from strong winds. Needs to be sprayed daily with filtered water, and fed (diluted fish emulsion) about every two-three weeks. Protect from slugs and snails. The Delta Maidenhair Fern is commonly found for sale in plant nurseries locally.

This plant is native to Costa Rica, Nicaragua, Mexico, Dominica, Jamaica, Trinidad and Tobago, Venezuela, Brazil, Bolivia, Colombia, Ecuador, Peru, Argentina, Paraguay, and Uruguay.


On May 6, 2005, nevadagdn from Sparks, NV (Zone 7a) wrote:

This plant overwintered for me, snow and all! I'm guessing hardiness may reach all the way to 8a. I have it tucked into a little "bog pocket" at the side of my above-ground pond, which never freezes solid in winter because I keep the pump running. I was very surprised to see new fronds emerging this Spring. I assume that the splash from the pond "waterfall" and ambient humidity that close to the water help me to grow this plant in otherwise arid Nevada.


On Oct 11, 2004, ladyannne from Merced, CA (Zone 9a) wrote:

We almost lost this one due to overwatering. It seems to like being much drier than the average bear.