Paeonia delavayi. Photo by Gregor Richardson.
One of the key projects in the Rhododendron Dell in spring
last year was the renovation of the Peony Border at the south
end of the Cherry Walk. Straggly old witch hazels were
removed, the border widened, a new selection of herbaceous
perennials planted and some of the peonies rearranged.
Among the peonies was a small, self-sown specimen of
Paeonia delavayi that had appeared at the back of the
border under the shade of Magnolia doltsopa. At that
stage, it was little more than a cluster of stems about 50cm
tall, with a few leaves attached. Now, after being shifted to
the front of the border, where it has more light, better soil
and improved drainage, it has at least doubled in size.
Peonies thrive in any moist, fertile soil, whether acid or
alkaline, but good drainage is important, particularly for
the shrubby types such as P. delavayi. The dramatic
increase in size shows just how well struggling peonies can
respond to improved soil conditions. Now that it is growing
happily, it will mature into a wide spreading shrub up to
about 1.6m tall, but if necessary, can be pruned hard to
control any intrusion on neighbouring plants.
Not only has the Peony Border specimen increased in size, but
it has also begun flowering quite freely.
Compared to other shrubby peonies, P. delavayi has
relatively small flowers, but they are a deep red and, along
with the smoky-coloured new foliage, look like hot coals. For
me, this makes this peony the one to plant.
- Doug Thomson is curator of the Rhododendron
Dell at Dunedin Botanic Garden.