BTW: Not that is matters much, but it is "she" not "he"
There has been a lot of experimentation with soils used for various CP species, both when a new species is introduced into cultivation and those who like to test conventional methods on species that have been in cultivation for many years. Cephalotus is a good example of a CP that can grow in a wider range of conditions including soil type than once believed according to posts I have read on TF alone and my own experience. Darlingtonia is another good example of this, again by posts from others and my own experience. I have read posts here and on other CP forums from people who grow Drosophyllum quite successfully in totally different conditions/soil types than me. In short, I totally agree that growing Drosophyllum can be approached differently than initial literature suggests, and there is so much yet to learn about this species.
I can relate to this, after growing darlingtonia from seed. Their roots were nearly 2 feet long on plants less than an inch in length, they were growing in highly fertilized soil (osmocote, the nitrogen high stuff), a top layer of living sphagnum and a soil mixture below of 90:10 perlite
eat and yes that's 90 perlite.
They were growing very fast and colored up quite well, darlingtonia seem to be happy if you keep them cool and in bright conditions.
Due to the extra work required to grow plants outside in my region, I usually grow strictly under lights, but drosophyllum seems to come from a climate that reminds me of where I live in Utah. Hot, intense sun and very little rainfall. I'm hoping to use this to my advantage by growing them inside for the fall/winter with as intense light as possible (florescent) and then moving them outside in the spring with the hopes that they will acclimate into the summer.
I suspect that I will use a higher peat ratio than is conventional to most droso growers, since the soil will likely dry out extremely quickly. In my region the humidity is extremely low and hot winds blow in the summer.
In regards to my inquiries about the soil composition and ion content of the water--
I'll be experimenting with coconut fiber. The reason is it's bulky and non-compressing characteristics. Coconut fiber was brought recently to the attention of Steve and Matt who grow VFT's, though it seems they've dismissed the media's potential due to a few logistical reasons such as looseness of the soil and possible leeching of minerals and the added work of initially lowering the TDS of the soil; however, if drosophyllum doesn't care about TDS, then
I don't care about it either.
It's possible that if drosphyllum tolerate COIR, then their conventional soil could be improved as the physical characteristics of COIR are often found beneficial. For instance COIR is made up of varying grades of particle which roots love. The media itself resists compression in favor of it's springy fibers and light weight. The setbacks are similar to those for its use growin VFTs: Better aeration means faster evaporation, and the coir may not have an optimal PH for the drosos.
I also see vermiculite as a second grade soil composition, as it breaks down over time and may contribute to compress the soil. The unfortunate side-effect of compression in soils is obviously to the plants roots. Since drosophyllum's roots are so sensitive, I think it's sensible to formulate a soil which shifts as slowly as possible from one state to the other i.e. decompressed to compressed such as COIR, PEAT, and VERM; fresh to broken down such as PEAT, LFSM, and perlite as it grinds against itself disintegrating and floats due to it's large surface area and hollow pores (which can be seen readily in a large bag of perlite).
It's possible that if bottom watered, pure sand would be the solution, however the setbacks are obvious such as frequent watering, lack of any nutrients, and even sand is poorly aerated if it has nothing to declump it (like bigger chunks such as perlite).
Pure sand mixtures should not be completely disregarded though, as I've germinated very healthy VFTs in pure silica sand before and their growth was comparable to plants germinated in peat and COIR substrates. COIR is interesting as it seems to accommodate cps which do not grow in "bog conditions" Drosos fall under this condition better than any CP I can think of.
I feel confident that by using COIR over peat, the soil will sustain these large and fast growing plants longer, it may allow the media to retain a more even moisture content without sacrificing the aeration so seemingly important in growing this species. I'm also skeptical of using such a huge amount of perlite in a soil as I imagine it all migrates to the top eventually, possibly disturbing roots and changing the soil consistency. Using more sand is usually a personal preference seemingly akin to the newer people in the hobby who see all the cool kids doing it (don't quote me here, but it does seem like experienced/older growers are less into sand and find perlite more convenient and economical). Perlite has been around forever, and using sand seems less mainstream.
I use silica sand, and I like it, but can you give me the synopsis/argument of using "playsand" and how you get it clean enough to feel comfortable using it? Are you one of those people lucky enough to have tap water which maxes out at 100 ppm or whatever and can just rinse the sand endlessly. If you are I'm jealous
With that said, it doesn't rain here pretty much ever, but if drosos don't mind ions in their water, then play sand sounds like a fun time, as it contains a component of some literature states about drosos in the wild. They are found in "loamy" soils, which basically means there is sand, silt, and clay in some combination. Silt and clay in play sand could hold water better than in pure silica sand which is basically siltless and clayless version of other sands.
There may be some who criticize the ideas I've presented. You can easily argue that perlite and peat are better because their PH and aeration balance are very good and economical. You are 100% correct and these are my initial thoughts as well. However, I enjoy contemplating the unexplored aspects in this hobby as the possibilities seem endless.
Dave,
I hope I'm not hijacking your thread, and hope to make a post one day how
I grew drosos and was successful, so far I'm unsuccessful after germinating 3/8 seeds two years ago and loosing them in the less than 5 leaf stage, but the day may come when we compare notes so to speak hahaha.