South African Succulent Gardens
New Zealand’s climate often provides ripe conditions for the unchecked expansion of South African plant species. Having developed in harsh conditions, many South African plants find the climate milder and benefit from quick growth and a lack of co-evolved predators. Succulents tend to do particularly well and have unsurprisingly escaped from the loose confines of gardens thanks to a historic trend of people using our beaches as garden waste dumps.
Anyone familiar with the coastline and cliffs of Wellington will have noticed a powdery blue cloak of pig’s ear (Cotyledon orbiculata) which erupts into flower in summer with an umbrella of nodding peach flowers. On a recent visit to Cape Palliser, this plant was profusely coating the surface of the backshore cobble-field. It had also found refuge on the acidified understory of pine plantation, showing off its capacity to grow just about anywhere. A succulent ‘garden’ perches on the cobble-field with African boxthorn forming a band along the foreshore, likely an old stock hedge planted by early European settlers. A South African species which aggressively spreads throughout the coast, the translation as thorny and ferocious is an obvious one to anyone who has encountered it. It wrestles for the same niche here as native taupata (Coprosma repens) which has begun recolonising. Together they form a low two-tone edge to contrast the lighter fuzz of native ground-hugging species like pohuehue (Muehlenbeckia complexa). Undulating brown hummocks are pierced by the spiny, thick-leaved māhoe (Melicytus crassifolius). Fluffy cream heads of bunnytail grass (Lagurus ovatus) help create a layered separation between plants and together with pig’s ear and Agapanthus praecox, the whole composition takes on a coastal wildflower aesthetic or that of grandma’s unkempt bach.
These writings on hybrid plant communities are not meant to encourage the planting of the same species, many are invasive and inhibit the niches for native species. Instead these are meant to highlight natures ability to compose plants in a given climate and geology, whilst offering alternative native species or non-invasive exotics to achieve similar effects in the garden. Sensible native replacements for the exotic grasses include Poa billardierei and Dichelachne crinita. The boxthorn as already mentioned can easily be replaced by taupata and to achieve the blue and orange tones of pig’s ear, Euphorbia glauca or Aciphylla sp. could be substituted.
