I don't think you will have much luck with Protea subvestita in Rhode Island conditions even if you do manage to find a source. This species is more used to just occasional freezes in habitat and not weeks at a time, and also won't like the humidity in summer of your location. I'd recommend growing more commonly available species as container plants, and pull them into a cool greenhouse for the winter, one that also has fans going for good ventilation in winter and is heated to 40 or 45F at night in winter and into the 60'sF in the day. They would do well for you under these conditions as long as your summers aren't too humid in summer, and you gave them the special soil mix conditions and fertilizer regimen that they need as container plants. There aren't really any South African Proteacea shrubs in the Protea/Leucadendron/Leucospermum species that are going to do well with East Coast USA conditions, although they do manage to grow them in the display greenhouse gardens at that large private botanic garden outside of Philadelphia, I can't seem to recall the name. Essentially they are growing them as a controlled greenhouse plant that seeks to replicate summer/winter Mediterranean climate conditions and is full of typical outdoor California garden plants such as Acacias, Agapanthus, Proteaacea shrubs, Tibouchina, etc. They do heat the greenhouses to keep them above freezing in winter, but not tropical hot house warmth, and also cool the temps in summer so they are not so extreme as outdoors in summer. The few Protea members that aren't native to South Africa's Mediterranean climate zones are all montane species that would be accustomed to cooler nights in summer due to altitude, and little winter rainfall, no weeks long subfreezing temperatures without daytime warmup, and daily temperature fluctuations year round rather than hot nights. This is difficult to replicate at sea level along the East Coast USA.

I should watch this thread more closely as there are so few of us who share the common interest of Proteas for the Pacific Northwest, and I would hate to lose touch! The South Island of New Zealand has a Protea Growers Association of 60+ members; I think we'd be lucky to get five around here. Iyou - I think there's hope. I heard from a guy in the Grants Pass, Oregon area that Banksia repens survived the big freeze last December (bottoming at 12F for him) without a scratch with only a bucket over it for protection. This species from Western Australia does not even come from an area of severe cold yet it seems at least as hardy as any of the eastern Australian Banksias from the Snowy Mountains. I know that doesn't really prove anything in itself, but I like to think that if one compares Banksias to the Protea situation in South Africa, I can be optimistic that some of the more obscure high altitude Cape species (for example, recondita, venusta, cryophila, humiflora, witzenbergiana) might be hardy enough for us. So far I have recently planted seed of P. venusta and P. humiflora, but humiflora hasn't germinated - perhaps they will come up in the fall. Venusta has produced seven seedlings so far. I'm expecting some variation among the plants so I plan to keep them all and compare their ornamental qualities before propagating them to test for cold hardiness outdoors and to sell. I also just got some seed of P. effusa which is another exciting, obscure high altitude Cape Species. That's interesting to hear about P. caffra thriving on clay - thanks for mentioning it! Still, the Drakensberg is so dry in winter that many plants from there will grow in Denver but not Seattle - I bet clay soil with heaps of winter rain and the occasional Northwest Arctic blast will be an unworkable combo. My idea is to someday build raised beds about 2' tall and bring in a soil mix. I was thinking of using something like 2 parts sand, 2 parts red lava rock and 1 part compost for the Cape species, though I really don't know how that will work out (perhaps I'll try it in a smaller area first) and compare the results in that raised bed with plants planted directly into the native soil (a loam/rocks mix). I'm just full of ideas... LOL. If you know of any Leucadendrons that actually survived last winter in Portland without freezing to the ground, I'd love to hear about them. My experience with the more readily obtainable cultivars (which are mostly of L. salignum and L. laureolum parentage) is that they invariably die in our climate below about 20-24F. A lot of them are certainly hardy through our mild winters, so perhaps I can get these hybrids to put on some size before a cold winter puts them to the test.

Joe, Brave of you to try these. I have been experimenting with protea from seed for some time. It's true that some seem to damp off the minute temperatures get high. But I think there is some variability, this year I have had a Protea subvestita seeding survive so far. Even though this summer in DC wasn't very hot, it was still much hotter and more humid than the alpine habitat of that species, which is probably something like 72/52f in the summer. Based on my analysis of the various summer rainful species, and my general experience growing SA plants, I'd also recommend you try Protea caffra, gazensis and simplex. But these, unlike P. repens, are summer-rainfall species and would be helped by building a winter rain shield if your area has heavy winter rains. Remember that phosphorus containing fertilizer will kill them, you probably already have read that but it's easy to be fertilizing a nursery tray and accidentally keep pouring. Good luck!

There are many hardy and potentially hardy SA plants that could be grown in northern Virginia. In addition to those already mentioned, Albuca shawii, Artemesia afra, Phygelius hybrids/species, Berkheya purpurea, some Crocosmia spp or cvs,some iceplants like Delosperma sp Basutoland (yellow flowered sp formerly sold as congestum) and D. cooperi, the variegated leaf form of Tulbaghia violacea, and Nerine bowdenii are some I have had success with in the suburbs of NYC. You might also consider, in full sun with leaf mulch for winter protection, Pelargonium luridum, mimimum, reniforme, ionidiflorum, some forms of alchemilloides, and dichondrifolium. Luridum will definitely survive if the ground does not freeze too deeply and come up again in late spring. Many SA plants can behave as resowing annuals, among them in my small garden is a Nemesia species with small white or pale pink flowers (a similar thing is often sold in baskets in garden centers), Senecio inaequidens (a floriferous daisy with lots of small yellow flowers in fall which I collected in SA), and Commelina africana (a yellow flowered dayflower). This year I am hoping to see if Leucosidea sericea is hardy, one is outside and one moved inside after it froze in the pot during a night in the low 20's. It was not damaged, still has good leaves. Galtonia candicans is reliable and blooms every year. If winters are mild, other things may survive--in the Bronx in a sheltered position with leaf protection I had a seedling of Protea subvestita make it through an el nino winter. Planting certain things like iceplants and some bulbs in a sandbed is helpful for things that dont like soggy soil in winter, and a mulch is usually appreciated. Eucomis bicolor is another rather amazingly hardy plant,but it only wakes up when the weather is really warm, so dont expect to see it before June. Good luck! Ernie