I am not sure whether it’s because when times are tough we often gravitate toward nostalgia, but as I browse the seed catalogues this winter, I am thinking wistfully about busy lizzies. This lush, free-flowering, easy-to-grow genus from cool, highland rainforests was once one of the most common bedding plants for shady spots. Yet in the past decade an outbreak of a new and deadly fungus-like disease – impatiens downy mildew – led to a collapse in demand for these plants.
Deadly as it is, the disease appears to be extremely species-specific, centred squarely on Impatiens walleriana, which made up probably 99% of the market. Discovering this, plant breeders worked to create new varieties by crossing the susceptible species with other close relatives to create plants with a much higher genetic resistance. As a botanist, I do wonder: why the over-reliance on a single species? There are about 1,000 species of impatiens, many of which are far more striking and exotic-looking, and just as easy to grow. Rather than a disaster, could this be a much needed spur to open our eyes to a huge diversity of possibilities that we have been missing?
The usual disease-resistant option recommended is Impatiens ‘New Guinea Group’, as its larger flowers and often striking foliage work brilliantly not just as bedding but as houseplants, too. But there are so many more varieties we could be experimenting with, both indoors and out. I have a soft spot for I niamniamensis, the ‘Congo cockatoo’, with incredible, orchid-like blooms shaped, as its name suggests, like little parrots.
I parasitica is an exceptionally rare species from India that grows clinging to tree trunks. With shocking, almost dangerous-looking flowers in green and red, with hooked “tails”, it sits as if poised to fire a poison dart at you. When I saw this was sold by Welsh growers Dibleys Nurseries, I was so excited that I nearly fell off my chair.
If you are looking for something friendlier, there is I bequaertii, the dancing girl impatiens, which has adorable pale pink flowers shaped like a person with outstretched arms and a flowering skirt. Finally, I can’t resist telling you about I kilimanjari, which looks rather like a cross between I parasitica and I bequaertii. With cheerful fuchsia-pink and orange flowers that have a jelly-bean like translucency, and with a quirky curved green “tail”, these are impossibly exotic and reassuringly pretty in equal measure. And there are hundreds more busy lizzies to discover. If you are hoping for new beginnings this summer and exploring options for resilience, there is no better genus to try growing.
Follow James on Twitter @Botanygeek
