Capensis fertilization experiment

I tried an experiment adding osmocote to the soil of D. capensis. 2 week old seedlings were transplanted from germination trays on September 19th, with 12 pots per level of fertilization:

0 (top row), 1, 2, 3, or 4 (bottom row) pellets per pot. Growing in a mix of peat and perlite. This experiment didn't rate being under lights, so I put it in a very sunny window at work.

Remarkably, none of the fertilization levels killed any plants- I thought for sure 4 osmocote pellets per pot would be damaging. In fact, that was my intention- get the full range from 0 to deadly.

Anyway, as you can see, there does seem to be an effect. The 0 osmocote plants are much smaller than those with some osmocote, though there does not seem to be any effect of increasing the dose.

One major caveat to this experiment is that there is among-treatment contamination. I used a single 1020 tray, so all wells shared the same water source. In the beginning this water source had about 70ppm solutes, which was mostly fertilizer as I was using RO with 4 ppm as my watering source. So even the 0 treatment got a lot of nutrients. Given this, I'm surprised that there are effects of adding a single prill per pot- though perhaps those nutrients are less mobile and are binding to cations in the soil.

The verdict: I'm tossing osmocote or nutricote (mostly using this one as I think it is even better) in all my pots these days- sundews, VFTs, even nepenthes. I have only killed a few plants doing this (due to defective prills- some dump all their fert immediately, rather than doing time release), and even then, plants a half cm further away were fine and in fact grew super well. So the effect is very local.

Enjoy experimenting with fertilization! For me, it's been a huge power-up.