Growing Guide: Nepenthes Media (Updated)

Seramis clearly visible in this N. jacq. hybrid's pot

Several months ago, I posted about my (new) preferred growing medium - 1:1:1 mix of Seramis: Leca Clay: Lava Gravel. Well, it turns out, this medium is not for all plants. I've been worried for some time about my Nepenthes bicalcata x ampullaria, which has refused to put out a single new leaf for me. I recently decided, based on the valued input of other growers, into long-fiber sphagnum.

At the time I advocated the Seramis mix, I mentioned that Seramis doesn't seem to be sold in the United States any longer. Since that time, I've been in contact with the good people at Seramis, who informed me that they no longer distribute to the United States, but did give me the contact info of their Canadian distributor, who, as of this posting, has not yet let me know whether he can ship to the United States (though my guess is "no."). As a consequence, when my Seramis runs out, I'll be looking for a new media mixture.

Seramis, as some of you may know, is actually a slightly-alkaline, clay-derived, substance which slowly leaches minerals. I've found that my plants do appreciate the added nutrients and I've seen substantial growth from plants potted in the Seramis mixture (though I've observed such growth from every plant which is treated with fertilizer, so I'm not sure the Seramis does much).

Since the key component of a Nepenthes mixture is airiness which retains water, I will probably be experimenting with Seramis substitutes, such as perlite, to see how they work. (Although I'm not sure what will withstand the rigors of time as well as the current preferred growing medium).

For any of you using my preferred growing medium, I've found that a thin top dressing of sphagnum (living or dead) is a great way to retain more moisture in this quick-drying medium. If you use dead sphagnum, consider adding another plant (I typically use U. livida) to anchor the sphagnum to the medium. I find that allows the pot to be knocked around a bit more before the top dressing falls off.

However, I would not recommend this mix for swampy Neps - e.g. bical and ampullaria, as well as hybrids with those species. It's not a mixture that works well. It does seem, however, to have no effect on aristo hybrids, dubia, or most highland plants that I've tried it on. In a few months, I'll do an update on the bical x amp and, if it has improved, make up a table of planting medium for each Nep in my collection, to show what species like what medium