When is a Kangaroo Paw not an Anigozanthos...

...when it's a Macropidia fuliginosa or more commonly, Black Kangaroo Paw.



This spectacular Western Australian Native is the only kangaroo paw in it's genus while the more familiar Anigozanthos has several. M. fuliginosa has the same requirements as other Kangaroo Paws, such as good drainage and a preference for lighter soils. Though it flowers mainly in Spring and early Summer it doesn't always follow the rules and can even put on a display such as this mid Fall.

M. fuliginosa is just as susceptible to ink spot disease as other kangaroo paws and can be avoided by irrigating either early in the morning or via drip, keeping moisture away from the leaves. Black tips are also common and seem to be unavoidable regardless of which kangaroo paw you choose. I like to surround the plants with other dry climate Australians such as the evergreen Lomandra species. The strapy green leaves do a great job of hiding the plant when it's not looking it's best and provide the Ta-Da platform when the flowers emerge.

I've grown M. fuliginosa in both the ground and in pots and it does well in both when allowed to dry out a bit in between waterings. ASGAP states "... species die back to the rhizome in summer, regenerating in autumn". I've not been brave enough to test this in my garden as these plants are hard to find in the first place.

Acacia Friend or Foe

This is the first post on this blog and I have so many plants to write about that it was hard to choose which species to cover. The decision was made clear when I recently talked with a client about adding an Acacia to the design and was met with a look of horror. Words such as "Allergies" and "Invasive" rattled away as the floral emblem of Australia took a backward step and said "Whoa man, I'm just misunderstood". So for the first blog I'd like to start by breaking down some misconceptions and spreading the good word about this little golden wonder.

Allergies

The best part about having an Acacia is also the major cause for concern to homeowners. Those soft fuzzy balls that cover the plant each spring look incredible and are a boon for the bee population. Unfortunatley, it is also the most visible plant blooming when the allergies attack and quit often blamed for initiating them.

The reality is that the pollen from Acacias is actually too heavy to be blown any distance from the tree and relies on insects to move it about. The real culprit is more likely to be grasses or the masses of Juniper, Cedar and Cypress that are hanging on from the 70's. According to the Allergy, Asthma, and Immunology Foundation of Northern California, Inc. (AAIFNC) Acacia is ranked as a minor cause of allergies from February through to March.

Invasive Potential

Two species of Acacia are currently listed as Invasive by Cal-IPC and are common sights around the bay area.



Acacia dealbata (Silver Wattle - above) can bee seen growing in coastal areas or in riparian corridors. It spreads via rhizomes and seeds in favorable conditions.

The other being Acacia melanoxylon (Blackwood Acacia - below) which is a common site around Contra Costa County. Both are pioneer type plants that prefer a disturbed site and their role in their natural range is to fix nitrogen back into the soil.



Both of these species have been around for a long time and their invasive potential is well documented. Getting a little geographical is a good idea when looking to incorporate foreign plants into the landscape that haven't had a long background in this country. For example, I'm wary of plants originating or having part of their range in Tasmania. This is the stomping ground for Eucalyptus globulus (covering much of the East Bay) and not surprising the southern most range of both of the species listed above. So that is two of the 954 species growing in Australia that aren't suitable for our gardens, many others are so lets look at those.

Garden Worthy Acacias

Plant size is always a consideration in our urban gardens as we only have a certain amount of room to play with. History has shown that Californians generally prefer their trees on the small side which species such as Crepe Myrtle, Purple Plum and Japanese Maples being common place. With that in mind I'll discuss a few species of Acacia that are no taller than 15'-20', work well in a drought tolerant garden and are non invasive.

Acacia merinthophora



Also known by the common name of Zig-Zag Wattle, which came be problematic as there is another Acacia with the same common name that grows a lot larger and is distinctly different. A. merinthophora is a very light and airy small tree or large shrub growing to 12' high and about as wide. It prefers a location in full sun with medium to good drainage and is extremely drought tolerant when established. It's natural range is the arid interior regions of south-Western Australia that shares a similar climate to ours.



During the parts of the year when this plants is not in bloom it holds interest in both the long coarsely textured leaves as well as the striking gold bark of the season old branches. This is one plant that always gets attention with passers by and doesn't mind being man handled by those who need to get a little textural sensation from their plants.

Acacia glaucoptera (Clay Wattle)



Clay wattle generally tops out at 2-3' and spreads out to 6' or there abouts making it an ideal ground cover. It's natural range is also in Western Australia however it is more southerly than A. merinthophora and is a little more cold tolerant. New growth occurs in the cooler months and has a distinct reddish tinge that contrasts well with the deeper green older growth. This is also and extremely drought tolerant plant once established and even though the common name has 'clay' in it this little grower still prefers good drainage.

Acacia vestita (Weeping boree or Hairy Wattle)



Weeping boree is another small tree to between 12-16' to slightly wider that grows in open and lightly wooded areas of central west - New South Wales on the east coast of Australia. The golden ball flowers appear in Spring at the tips of soft hairy phyllodes (Leaf-like flattened stems that replace leaves on mature plants).

Acacia boormanii (Snowy River Wattle)



Snowy River Wattle grows to about the 14-16' mark on multiple stems producing golden ball-shaped flowers in spring. It's range is centered around the mid altitude mountain areas in South Eastern Australia. When in flower this plant is an incredible sight that steals the scene regardless of where it is planted. Once the bloom is over it tends to to sink into the background waiting for the following Spring.

Acacia cognata (River Wattle)



River Wattle (above left) is a few feet taller than the species listed above but is worth considering for the larger garden setting. It can grow to 25' but more commonly tops out between 14-18' and about the same width. The habit is similar to Mexican Weeping Bamboo with its soft long leaves and willow look.

Quite a few prostrate forms of the species are sold in Australia but I have yet to see them on the market here. Here are some that would be worth growing:

Acacia Cognata 'Limelight'



Acacia cognata `Fettuccini'



Now that you've stopped sneezing and know which Acacias not to plant, maybe you'll consider one of these plants for that bare dry spot in the garden.