Orange Horror a Blot on the Landscape
California poppy infestation along a Canterbury braided river
Californian poppy might look delicate, but it’s spreading like a rash though some parts of New Zealand and causing strife for some small native plants and grasses.
This ‘pretty’ poppy opens its bright yellow to orange flowers to the sun and has become a bit of a wildflower favourite, popping up in all sorts of places, from roadsides to gravel riverbanks, stony soil and poor pasture. It forms a small, tufted rosette with grey or blue-green foliage, and the papery flowers are followed by ribbed seed capsules that contain numerous small black or dark brown seeds.
Californian poppy might look delicate, but its growth habits are anything but. It spreads into areas where many other plants wouldn’t, but these habitats are also ones where some of New Zealand’s small native grasses and herbs call their own. In particular, California poppy is a threat to these plants in scree slopes and subalpine herbfields. It tolerates hot, dry conditions, rapidly colonises any bare, sandy or gravely, dry or well-drained soils in open, sunny positions and has found its way into many wild areas, including tussockland, braided rivers, dunes, coastal cliffs, pastureland, roadsides, scree slopes and subalpine herbfields.
The simplest way to control California poppy in your garden is to cut off seedheads before they ripen, and to ensure that these seedheads are disposed of at a refuse transfer station. If this is too much bother, remove the entire plant, and find non-weedy alternatives to take its place. Your local garden centre will be able to advise on suitable non-weedy species for your local growing conditions. Control methods for infestations in areas outside your garden can be found here.