Going for gold

Sunday, 16 March 2014

Golden heliotrope

I have previously written a blog about golden leaves in the garden, but I had to omit many of my favourite plants - and since that time, I have acquired some new specimens that are doing well. The longer I garden, the more enamoured I have become of decorative foliage. Unlike flowers, which come and go, foliage remains (more or less) all year round. There are so many attractive colours and patterns in foliage plants that grow well in Sydney: an interesting garden could be created using these sorts of plants alone.

Xanthosoma Lime Zinger with Colocasia esculenta Black Magic in the background

I particularly like golden leaves because they light up the garden (especially those that will tolerate shade) and plain gold foliage has great potential for making colour echoes with other plants: emphasising the colour of flower petals or stamens, or spots or stripes of variegated leaves - as well as being a feature in itself. Many so-called golden plants are lime-gold, especially when grown in shade - a colour I really like in the garden. My most recent acquisition is limey-gold 'elephant's ear' type of plant with huge dramatic arrow-shaped leaves. Often called Alocasia 'Lime Zinger', it seems to be more correctly Xanthosoma 'Lime Zinger' (ht 1 m). I grow mine in a pot in part-shade but it can be grown in the ground with the protection of an overhead canopy - to prevent sun scorch in summer and shield it from frost in winter. It grows from a rhizome and needs moisture to do well. I have mine nearby to a potted specimen of its cousin Colocasia esculenta 'Black Magic' and I like the striking contrast of leaf colour yet the close similarity of form: the dark one being almost like a textured shadow of the other!

Coleus cultivars (Solenostemon)

This past summer I obtained a very bright lime-gold coleus, which has grown well in a shaded part of my garden, really brightening up the area with an incandescent glow. I have paired it with another new delightful coleus that has dark red leaves with a golden edge, and I enjoy this combination. Some coleuses do not survive our winters - I try to remember to take cuttings around this time of year of my special favourites and keep them sheltered in winter. I also grow a gold version Talinum paniculatum (ht 60 cm) in shaded spots in the garden to enliven the areas. This is a perennial that dies down in winter then reshoots in spring. It self-seeds very enthusiastically, so I have a number of them dotted around my garden, but I like finding these unexpected patches of gold.

Coprosma repens cultivar

Several years ago, I obtained a gold-variegated Coprosma repens (ht 1 m), but alas I have forgotten its cultivar name. I have never had much luck with these evergreen shrubs in the past and this one seemed to suffer a fair bit of dieback at the end of its stems at first. However, it has now settled in and forms a striking mound of glowing, shiny foliage. Some stems have reverted to plain gold, which I don't mind. In summer it forms a background to a variety of bright yellow Rudbeckia daisy plants, and in winter it partners with the fluffy yellow heads of Justicia aurea. It is also effective with blue flowers, such as the self-sown Browallia americana that have popped up around it.

Golden oregano in the kitchen garden at Heide II in Melbourne

Other easily grown plants with golden leaves include the golden form of oregano (Origanum vulgare 'Aureum', ht 30 cm), which forms a wide mat of tiny rounded leaves. It grows best in a dry, sunny spot and needs to be reined in every so often to stop it taking over too much territory. The golden form of heliotrope (Heliotropium arborescens 'Aurea' ht 75 cm, pictured at the start of the blog) is also a useful foliage plant. It is more chartreuse in colour when grown in semi-shade, as mine is. It doesn't flower a lot but I grow it for the pretty, textured leaves. Grassy-looking Acorus gramineus 'Ogon' (ht 30 cm), which actually belongs to the same family as the Xanthosoma, is one of my all-time favourite golden plants. It has soft, gold-striped leaves and will grow in sun or shade, as long as the soil is not bone dry, and gradually forms a nice clump, but it is not invasive. It is an excellent contrast to any broader-leaved gold-leaved specimen and looks good every single day of the year. What more could we ask of a plant?