FlytrapCare Carnivorous Plant Forums

I've long wondered what the best soil is for flytraps so this year I decided that I'd to try and put it to the test.

I set up 3 containers with 9 rhizomes of B-52 flytraps each. The rhizomes were all approximately the same age and size. I kept them in identical conditions and fed them on the same schedule to ensure the cultural conditions were as close to identical as possible.

The significant difference was the soil:

• 1 peat : 1 perlite - This is the standard mix that most people use and I just filled up the pot with it. The perlite was fairly fine and around the 1-2 mm range. I measured out the ratio by dry volume.
• 1 peat : 1 perlite but the rhizomes of the plants are all wrapped in long fiber sphagnum moss - The moss extended to the bottom of the pot for each plant. To do this I filled the pot with 1 peat : 1 perlite and once it was full then dug out 9 holes to the bottom of the pot about as wide as my hand and filled that with 1 sphagnum : 1 perlite wrapped around the roots of the rhizomes. Maggie Chen reccommends this approach and claims it's supposed to be almost as good as pure sphagnum so I really wanted to give it a try.
• 1 sphagnum : 1 perlite - This supposed to provide best growth and is certainly the priciest option. I think filling up this pot alone probably cost $20 at least.

I've kept each of the 3 pots in identical conditions and watered them on my ebb-and-flow watering table this season, which means about every other day the 12" tall pots get flooded with rain water up to about the 6-7" mark. In retrospect, I don't think this provides enough moisture to the top of the pot since the sphagnum top dressing constantly looked fairly dry. Next year I'll probably try using 20 oz styrofoam cups since top of the soil colum is lower and stays moister from this watering approach.

Anyhoo, here are the results so far. As expected, the 1 sphag : 1 perlite is doing the best.

Surprisingly, the peat+sphagnum is doing the worst of the them, which is not what I was expecting. Maybe this is a result of how I'm watering the plants. I don't know.

Another great experiment - thanks for doing this!
I was using pure sphag but I didn't like the way the sphag turned hard and crusty on top and waterlogged/saturated and too dense/packed underneath, maybe the perlite helps aerate and lighten the sphag.
I'm now trying a peat, chopped sphag, perlite and sand (12 & 20 grit) mixture on an SD Kronos re-pot - has a nice lite spongy feel in my hand and is easy to use. This SD Kronos must have still been on the "juice" with thirteen divisions separated from the main rhizome in six months growing in every direction like a "pig tail".

Yep, you're spot on. I added the perlite to the sphagnum moss thinking it would help prevent compaction. It also helps by adding a bit of volume so the sphagnum goes a little farther, which based on the crazy price increases recently has helped my budget some.

It'll be interesting to examine the roots in the spring next year when I repot them and I plan to provide an update to this thread around that.

Your soil mix sounds interesting and I'm very glad to hear that your SD Kronos is liking it! I've moved away from using sand recently since it seems like it's difficult to find in the right size and adds a lot of weight (and compaction) to the soil mix. Would love to see a side-by-side comparison between that and the sphagnum/perlite, though!

Dan V wrote:Another great experiment - thanks for doing this!
I was using pure sphag but I didn't like the way the sphag turned hard and crusty on top and waterlogged/saturated and too dense/packed underneath, maybe the perlite helps aerate and lighten the sphag.
I'm now trying a peat, chopped sphag, perlite and sand (12 & 20 grit) mixture on an SD Kronos re-pot - has a nice lite spongy feel in my hand and is easy to use. This SD Kronos must have still been on the "juice" with thirteen divisions separated from the main rhizome in six months growing in every direction like a "pig tail".

Hmm, I just realized I posted this in the wrong forum. Could a moderator please move this to the Water Quality, Growing Media, and Planting Containers sub-forum?

For me, I would recommend sphagnum with perlite for Nepenthes because it is not compact and it gives an airflow to the roots of the nepenthes. I do not have experience keeping venus flytraps and other carnivorous plants except sundews and Byblis liniflora but both died.

Any notable changes in the last month, Davin?

Nothing unexpected. I can post some more pics tomorrow but the general trend has continued... sphagnum's the best with peat/perlite 2nd and peat/sphagnum 3rd. I had to move some plants around to keep them safe from the hurricane winds but should be back to normal tomorrow.

;No need for the pictures, but of course feel free to post them. The trend continuing says it all.

You get them anyways!

Here's the latest...

Great work, I am going to try spaghnum/perlite mix based on your results.