Ahinahina, Haleakala Silversword
Argyroxiphium sandwicense subsp. macrocephalum

Family: Asteraceae (ass-ter-AY-see-ee) (Info)
Genus: Argyroxiphium (ar-gy-roh-ZIF-ee-um) (Info)
Species: sandwicense subsp. macrocephalum

Category:

Perennials

Shrubs

Foliage Color:

Silver/Gray

Bloom Characteristics:

Unknown - Tell us

Water Requirements:

Unknown - Tell us

Where to Grow:

Unknown - Tell us

Height:

18-24 in. (45-60 cm)

24-36 in. (60-90 cm)

8-10 ft. (2.4-3 m)

Spacing:

18-24 in. (45-60 cm)

24-36 in. (60-90 cm)

36-48 in. (90-120 cm)

Hardiness:

Not Applicable

Sun Exposure:

Full Sun

Danger:

N/A

Bloom Color:

Pink

Purple

Bloom Time:

Mid Summer

Late Summer/Early Fall

Mid Fall

Late Fall/Early Winter

Foliage:

Velvet/Fuzzy-Textured

Other details:

This plant may be considered a protected species; check before digging or gathering seeds

Soil pH requirements:

Unknown - Tell us

Patent Information:

Unknown - Tell us

Propagation Methods:

From seed; direct sow outdoors in fall

Seed Collecting:

Bag seedheads to capture ripening seed

Gardeners' Notes:

3
positives
0
neutrals
0
negatives
RatingContent
Positive

On Jul 15, 2010, kaulanaH from Kamuela, HI wrote:

i apologize for my mistake, im new to "daves garden" but i do live in hawaii, n i kno just about all of our endemic plants, if your looking for ahinahina you wont find it elsewhere, keep in mind that there are atleast five that i can think of at the moment species of ahinahina, all of which are protected by state AND FEDERAL LAW ANYONE WHO TAKES ANY PLANT MATERIAL ie:seeds, flowers, small plants. FROM THESE SPECIES ARE BREAKING STATE AND FEDERAL LAWS.
anywho...:) it is also one of my favorites, silverswords are endagered and for them to thrive in the wild plants must cross pollinate, if not the plant will produce in-viable seed which are bourne upon achnes.

Positive

On Feb 27, 2005, foodiesleuth from Honomu, HI (Zone 11) wrote:


`Ahinahina (Hawai`i’s native silversword plant) is noted for its silvery radiance and sharp spiky ball shape. The silver hairs on its rigid sword-like leaves help prevent it from burning as it reflects ultra-violet light and also help the plant to capture moisture from the morning dew.

There are three species of silversword, found on the slopes of Mauna Kea, Mauna Loa (on the Big Island of Hawaii) and Haleakala on Maui. It is believed that the silversword is a distant relative of a California Tarweed which made it to Hawai`i on its own and over many centuries has evolved into the unique plant we see today.

Upon maturity after twelve to fifty years, the silversword will produce a five-foot-tall stalk from its center covered with hundreds of one-inch f... read more

Positive

On Feb 26, 2005, Equilibrium wrote:

I rate this plant a positive for its rareness however growing it isn't going to happen for you unless you live at an elevation greater than 6,500'.

There are two recognized subspecies of Argyroxiphium sandwicense; A. sandwicense subsp. macrocephalum has a more elliptical-looking inflorescence than A. s. subsp. sandwicense, which is thicker. Native to Hawaii, Argyroxiphium sandwicense subsp. macrocephalum is found only on the island of Maui up on the Haleakala volcano in and around the crater at elevations greater than 6,500’. The plant will only flower once in its lifetime which is around 20 years. The flowers will appear mid summer to early winter. After the seeds disperse, the whole plant dies. Their cultural requirements (the plant will not survive at lower elevations)... read more