Sweet South African Surprise-- Hymenolepis crithmifolia

Klair 2013- Green Planet

Many great plants for our California gardens come from South Africa, particularly from the Western Cape because they have a very similar summer-dry climate to San Diego.  One such treasure is Hymenolepis crithmifolia. Before that it was called Hymenolepis parviflora, and before that, Athanasia parviflora, or simply Golden Coulter Bush. Those botanists! Always renaming plants and making me learn new names when I had the old ones down pat. This is considered a shrub and is from the magical Western Cape of South Africa. The botanical description has the shrub reaching 2.5 meters with densely branched stems in the upper half of the plant. Most garden references list this plant as 1 meter or 3-4 feet tall. The leaves are super dissected or pinnatisect, with hair-like leaflets that start more of a silver/gray and mature as green. As fine as the foliage is, it is still leathery and sturdy. It seems that this progression is not in every plant. My plant stays much more gray-foliaged than green compared to some I have seen. I wonder if it has anything to do with the lack of water it gets from me? Here is a drawing from the South African Journal of Botany March 2014. Notice the individual fine-dissected leaf on the bottom left. Of the eight species in South Africa, Hymenolepis crithmifolia is the most common. 

A taxonomic revision of Hymenolepis (Asteraceae, Anthemideae) S. L. Magoswana and A. R. Magee

In a form of convergent evolution, this looks like a giant yarrow or Achillea. Funny how similar climates bred evolutionarily the same answers in plant form in Africa and also in coastal California. They have Hymenolepis crithmifolia and we have Achillea millefolium. 
Both plants have the tiny masses of mildly fragrant discoid flowers held at the ends of compound heads that are highly attractive to an assortment of bees, flies, and other pollinators. I like to just sit and watch the broad assortment of insects that love these flowers. So many are attracted to them. It is a regular golden dinner plate with tiny insects crawling all over the dense blooms. This evergreen plant blooms for several months in late spring/early summer. The blooms are lighter yellow when new and progress to golden yellow after a couple of months. After blooming you can cut it back to three feet to keep it garden-worthy. 

Silver gray foliage in my garden                                                                                                              S. Reeve

As you know silvery foliage and golden yellow flowers look great with many other plants. Think of foliage harmoney and juxtapose this with larger greener leaves. Combine with Lavender, Salvia x 'Anthony Parker', Salvia x 'Amistad', Cistus, Iochroma, Leonotis, and other Mediterranean plants. Golden Coulter Bush looks great with California natives like silvery foliaged Salvia leucophylla or Salvia 'Bee's Bliss'. I can see it skirting a Ceanothus x 'Ray Hartman tree or combined with Muhlenbergia rigens or 'Blue Glow' Agaves. What an exciting plant! So many possibilities for Hymenolepis crithmifolia. So much to like and so easy to care for. Prefers full sun, well-drained sandy loam soil and infrequent watering. I barely water mine, but it could be much fuller and more floriferous if I did. This plant is not frost tolerant preferring USDA Zones 9-11. Gophers and rabbits have shown no interest in nibbling on this plant. It handles the heat of late summer with no problem. It can reseed if you actually water with any regularity, which I don't. I am surprised this plant is not more well known and not more in use in San Diego Gardens. It is a lovely plant popular with pollinators, it combines well with others, which makes it a good plant in my garden.

Annie's Annuals                                                                                                                                  Annie Hayes