Last year in April I potted 6 medium-sized B52 Venus Flytraps with similar-sized bulbs, by first separating them into two groups of three, then planting each group of three into a 10-inch diameter pot. Both pots are identical polyurethane foam planters, and the Venus Flytraps have grown together in exactly the same conditions and with the same care regimen for the last 14 months.
The photo below was taken July 2, 2011. The 3 Flytraps in the pot on the left are growing in a traditional 50% sphagnum peat moss medium with 50% sand and perlite; the 3 Flytraps on the right are in a pot that contains a coir medium containing nothing but coir and (pure silica) sand.
Sphagnum peat moss and coir growing mediums comparison, 14 months of growth
To anyone who would like to try coir, a couple things to note are--
- "Coir" is a name that's thrown around a lot and means different things to different people, including the chopped fibers of a coconut husk (which is not what I use) and the pith that surrounds the fibers in the husk, that is normally removed and discarded during the extraction of the fiber intended for various uses including marine rope. This pith, sometimes called "coir dust," is what I use.
- Regardless of anything a manufacturer may claim, the coir must be thoroughly desalinated before initial use (I learned this from experience, not mere theorizing) by soaking the coir for 8-12 hours at a time (the water absorbs about as much of the remaining soluble material as possible within about 8-10 hours), then draing (testing for TDS, total dissolved solids) and discarding the water, and repeating the soaking and draining cycle 8 times or more until the TDS of the drained water is consistently under 60-70 ppm (parts per million), preferably around 50 ppm or lower (which is about equivalent to what sphagnum peat moss contributes in soluble material to the water in the growing medium). The water in the last few cycles should be distilled, rain water or reverse osmosis water to obtain a dependable TDS reading. Initially, in all 4 brands of compressed coir block I have tried, the TDS (total dissolved solids, as measured with a TDS meter such as the H-M Digital TDS-EZ, about $15.00 U.S.) of the drained water from the first soaking of the coir was over 1000 ppm, and sometimes over 1500 ppm, when the ppm we're seeking is ideally under 50.
Edited by xscd, 03 July 2011 - 17:06 PM.