Starting this thread because I know I'm not alone in loving these plants but I'm also in good company with those who find the culture of these plants a bit of a moving target.
Under my care is the following:
Minmaru (2 plants)
Minmaru-shima (2 plants)
Daruma chabo (1 plant)
Standard Sedirea (1 plant)
All of my plants are grown in moss-- mounded using the traditional Japanese method for neofinetia.
I live off a well and have tested the water several times since moving on to this property and the water is remarkably clean. PPM pre-RO/DI unit is roughly 60 PPM, post RO the water tests at 1 PPM. The plants get the RO water.
Fertilizer is applied at most, once a week. I use SOLO and at 1/4 strength and it is sprayed onto the plants, never dunked. The plants don't fill up the pot so I see no reason to dunk the plant. Spraying it allows the fertilizer to run down the roots and they don't seem to be heavy feeders anyway.
I grow mine under lights, for now. T8s, specifically. Since they are to be grown a lot like neos in terms of temp and even light, I will need to figure out a new arrangement for their overwintering since they apparently enjoy cooler temps during the off season. I may put them in my solar for the winter-- plenty of light and it can get fairly chilly at night.
Issues:
Roots! They like to stall...a lot. And then randomly, I'll get roots that seem unstoppable. I've been unable to figure out any rhyme or reason for it. One minmaru-shima is ailing and has been transplanted to sh culture and is cared for rather intensively, while the other, which also has stalled roots, also has plenty of NEW, OLD and growing roots. The regular minmaru seem more vital with their roots and the standard even more so. In terms of vitality (general robustness of plants) it goes:
1. minmaru
2.chabo
3. standard
4. minmaru-shima
In terms of root vitality it goes:
1.standard
2.minmaru
3. chabo
4. minmaru-shima
The standard plant is grown in moss as the others and seems to love it-- so much so i find it hard to tuck the roots back into the pot from the bottom opening.
The other issue I have is the moss-- it will often stay too wet inside and dry out too fast on the outside, so i try to make the moss mounds as thin as I can to get even drying. It also grows algae really fast for me. I try to go easy on the fertilizer as much as possible but that only helps so much. I know algae isn't avoidable, but its still really annoying.
Humidity: I grow in a smaller space but have one heck of a humidifier-- self-built-- it has five ultrasonic heads that pump moisture into the "closet" where my plants live. I can keep it at anywhere from 20% to 90% using a limit switch.
Temp: 70 at night to 88 in the day-- still trying to find out away to cool the room without humidity rather dramatically fluctuating. The only way to change it now is to turn on the exhaust fan OR shorten the photo period.
Photo period: I run my lights at night (cheaper to run at night) and run them in the summer for a pretty long time-- I think it's like 14 hours. I have already begun to drop the photo period down in 30 min increments to 10 hours at the peak of winter. No idea if this does much good or not but it's worked for me in the past.
That's all for now.