Drosera arenicola, ascendens, chrysolepsis, communis, gramminifolia, gaomogolensis, hirtella, hirtela lutescens, hirticalix, kaieteurensis, montana montana, montana var. tomentosa, montana var. schwackii, roraima, sessilifolia, villosa are all endemic to various parts of South America, and notably on the various Tepui’s there along with many species of Utricularia, Genlisea, Brocchinia, and Heliamphora. Beacause of the isolation, there is a high degree of speciation and variation within various populations.
As for how difficult they are to grow, the difficulties lie in being able to meet the requisite cool temperatures these species require to grow, along with high humidity and good light. Ideal maximums are in the 50F’s. The plants are also sensitive to root disturbance, and impure water. This means for most of us we have to be able to do some serious terrarium cooling, and use distilled water, and this involves hefty cash outlay.
However, like most plants, once they have what they need they grow. The hard part is providing what they need.
The greatest difficulty seems to be in acquisition of them. Close to a decade after the collections made by Fernando Rivadavia, they remain almost unknown in collections over the world. The plants are not autogamous, and do not generally self seed, and also require pollen from a clonal variant to effect fertilization, much as the petiolaris, D. adelae and D. binata do. They are all very slow growing, and may require several years to produce a flowering specimen. Seed has a very short viability window when it is produced.
Finally, these are some of the most mis-identified Droserae to be found, and the seed sometimes offered by various nurseries and seedbanks almost inevitably turns out to be a more common species like spatulata or dielsiana.
Sp. “emas” is currently a “bogus” species, meaning it has not been formally published. Taxonomists often work slowly. After 2 years of constant and diligent searching I have few species in cultivation, and my planned data base of seed testa photos will have very few of these species represented unless I can convince the growers of them to donate some seed for the project. To date, this has not been much forthcoming in spite of my efforts. See the headprints on that brick wall? They're mine.
This small victory has given me a little hope. With accurately ID’d digital scans of the seed coat, much time and expense can be spared by not having to grow out seed, only to find it is really spatulata, and seed banks and commercial dealers would have a way to keep more accurate control of what they send out. Good for us all.
Such is my hope! If anyone knows any potential sources for this seed, I would be very interested in hearing of it.