Ever since I had my first greenhouse at age 7, I’ve grown the tropical Green Cliff Break fern, Pellaea viridis. Never in my wildest dreams did I imagine I’d find a winter hardy form. It was not until 2005, when I visited South Africa, that we found it growing at a range of elevations from 2,500′ to 8,000′. After 22 years, we still have nine of those spore grown accessions in the garden. The plant below is our 4,200′ elevation collection of Pellaea viridis ‘McLear’, from near the town of McLear. As you can see, it’s made a stunning clump to 2′ tall x 3′ wide. We’ve discovered that Pellaea viridis thrives in a wide range of garden conditions, from moist to quite dry. Our happiest clumps are growing where they receive a couple of hours of full sun daily. While they may survive in deep shade, they certainly don’t enjoy it. Plant Delights still offer these amazing collections from time to time, but they never sell nearly as well as we feel they should. All of our current accessions have survived 7 degrees F in the ground, so we rate them as Zone 7b-9b, at least.
About four or five years ago I had a little clump of this randomly appear in my backyard in New South Wales, Australia. As I’ve always loved ferns, I regarded this as a wonderful gift from nature and nurtured it until I now have a thick and wild patch of lush ferns outside my dining room window. What surprised me the most is that it not only tolerates dryness, but it seems to actually prefer being left in dry ground for a couple of weeks where other species of fern would flag and wilt within days of drying out. In hot weather I’ve always kept it going with a watering can a few times a week around dusk.