Look up some information on wet stick propagation. It may be better off sitting on moist sphagnum moss in a humidity dome or ziploc baggie. I think it can grow another leaf but it will take some time. Also, I got some cuttings from brandtianum last year and they put out all tiny leaves for a while. I finally got one normal-sized leaf after about 5 months. I have the cuttings under a cloche.

”R”, are you in the Pacific North West, zone 8a? Maybe growth is slow due to the time of year, being Winter and all. I’m in sunny Southern Cal and growth is slow here for some of my plants.

Ken, these are planted in nursery pot that is inside the white decorative cover pot. These are sold by Costa Farms and I am well familiar with their system. Acacia, your plant looks fine to me. Make sure when you do water it that you take the plant in the nursery pot out, water it, let it drain before you put it back in the cover pot.

From what I understand, Birkins are the result of a relatively predictable, but unstable mutation that causes their distinct pattern of variegation. I cannot speak to what might cause them to revert to green or red type, which I know happens, but for many variegated plants, the level of variegated leaf area to green leaf area relates to the amount (amount is a vague term, but I'm not a lighting specialist so I don't know what the proper term is) of light the plant receives. Basically, if the plant is receiving light in excess of what it needs to perform basic functions, then there is a good chance that the next leaf the plant pushes out will be more variegated than the last. No leaf becomes more variegated over time. I don't know the exact mechanics of why this happens, but I think it's related to the plant being able to perform the necessary amount of photosynthesis with fewer photosynthetically capable cells (the green parts of the leaf). In terms of your lighting setup, I think this means you want to do some research into light intensity because I don't think the blue/red strips are considered very powerful grow lights. I'm currently reading Gardening under Lights by Leslie Halleck and I'd recommend checking out a copy from the library if you can. It's very accessible for hobby growers like myself. Sorry I couldn't help specifically with the Birkin reversion issue; I don't know much about it other than it's a bit unusual compared to other variegated plants.