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Black Wattle
Acacia mearnsii

Family: Mimosaceae
Genus: Acacia (a-KAY-see-uh) (Info)
Species: mearnsii (MEARN-zee-eye) (Info)




20-30 ft. (6-9 m)

30-40 ft. (9-12 m)

over 40 ft. (12 m)


15-20 ft. (4.7-6 m)

20-30 ft. (6-9 m)


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:

Full Sun

Sun to Partial Shade


Unknown - Tell us

Bloom Color:

Pale Yellow

Bloom Time:

Mid Spring

Late Spring/Early Summer



Other details:

May be a noxious weed or invasive

Flowers are fragrant

Soil pH requirements:

5.6 to 6.0 (acidic)

6.1 to 6.5 (mildly acidic)

6.6 to 7.5 (neutral)

Patent Information:

Unknown - Tell us

Propagation Methods:

From semi-hardwood cuttings

From seed; direct sow after last frost

Scarify seed before sowing

Seed Collecting:

Allow seedheads to dry on plants; remove and collect seeds

Properly cleaned, seed can be successfully stored


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


Gardeners' Notes:


On Nov 21, 2010, peejay12 from Porthleven, Helston, Cornwall
United Kingdom (Zone 9b) wrote:

I bought this plant originally under the name of A. filicifolia, but I think it is A. mearnsii - partly because of its hardiness compared to A. dealbata.

In Southampton, UK(Z9a) it survived -8c in a fairly exposed position while nearby A. dealbata died to ground level.
In Cornwall, (Z9b) I am now growing what I believe is the same species, and again it is growing well and survived a freak frost for Cornwall of -8C. It also retained most of its leaves.
Its hardiness would depend on where the seed was obtained as it is widely distributed along the south of New South Wales. But some plants grow in the Australian Capital Territory - parts of which can be very wet and cold during the winter.

I prefer it to A. dealbata because of its neater shape, and... read more


On Mar 7, 2008, htop from San Antonio, TX (Zone 8b) wrote:

I ahve not grown this plant. Black Wattle (Acacia mearnsii) has become naturalized in Hawaii and California.


On Dec 11, 2004, tonyf from Sydney
Australia wrote:

In Australia it is subject to borers and has a short life span of 5 to 7 years.