Temperate sundews that are cold hardy were the first sundews I became familiar with growing up on the Jersey Shore near the pine barrens. Just minutes from my house on the Great Bay, there were many bogs and lakes and sandy streams that were home to Drosera rotundifolia, intermedia, and filiformis var. filiformis (the three native species), and I had also seen the small patch of D. x hybrida at Lake Absegami, near where I lived. I discuss D. x hybrida extensively in my book The Revised Savage Garden, it is the rare natural cross between D. intermedia x filiformis ssp. filiformis. Only once had I found D. x beleziana, but at the time I didn't know exactly what it was. This is the natural cross between D. rotundifolia x intermedia. At California Carnivores we sell D. x beleziana 'Nightmare', a robust individual we propagate from leaf cuttings introduced by Ivan Snyder of Southern California, a plant he found near Tom's River, N.J. It has always been one of my favorites of temperate sundews, having hybrid vigor.
However I must admit the past couple of years I have been very impressed with another temperate sundew hybrid, however it was new to our nursery a few years ago and I neglected to include it in the revised version of The Savage Garden. This plant is Drosera intermedia x capillaris and was discovered in Virginia, a few states south of New Jersey, where the natural northernmost populations of D. capillaris are found. D. capillaris, commonly known as the Pink Sundew (due to it's usually pink flowers), is a warm-temperate sundew that does not produce hibernacula winter buds. Usually this species survives frosts but hard freezes kill off the plants in it's northerly ranges, but it comes back the following spring from seed. However the hybrid of D. intermedia x capillaris does produce rather robust dormant buds, and the plants themselves are deep reddish purple in color with spoon shaped leaves in dense clusters. The rosettes can reach two to three inches in diameter. The flowers are the palest pink to white, but do not produce any seed, being, as are most sundew hybrids, infertile. But the plant can be easily propagated by leaf cuttings taken in spring so the budding leaves have enough of a growing season to grow to a survival size by autumn.
Another thing about this plant that I love is how readily it produced clumps in cultivation. If you have one plant this season, by next year you will have two or even three or four closely growing together, and of course the dormant buds in winter are the easiest way to separate them. This hybrid has become one of my favorites of the small rosette sundews that are cold hardy.
I looked up this hybrid on Wikipedia and it was not listed. Bob Zeimer's database of photographs of sundews in cultivation (found on the society's web site www.carnivorousplants.org) had a number of photos of this hybrid, but to be honest, I looked at about a third of the photos and none impressed me like the plant in real life. Most of the photos showed shade grown greenish plants probably grown in greenhouses, and one photo of this alleged hybrid looked more like a true D. intermedia than this cross. I regret not having included it in my book!
I should mention that this hybrid does require fairly cold winter temperatures. They do best outdoors in full sun, and are perfect for bog gardens. Usually winters in Sonoma County where California Carnivores is located has average January night temperatures in the 30s F (about 2 to 4 C) with highs in the 50s F (about 12 C). The greenhouse never drops below around 50 F (10 C). But this past winter was an exceptionally warm one, with winter highs almost consistently in the 60s to 70s F (20 to 25 C). What we found was that colder temperate sundews like D. intermedia x capillaris and D. x hybrida that were kept in the greenhouse all winter had their hibernacula die in such warm weather, while the outdoor plants with colder nights and cooler days all survived beautifully. Therefore respect the winter dormancy of this beautiful hybrid and you'll find it a great and easy plant to grow.