Paph. micranthum resting care

[Masaccio]

I've had a single growth micranthum for a couple of years. It's growing very nicely. My first question is whether micranthums bloom off of healthy, sizeable single growths? If so, the second is about resting it to encourage bloom (which it hasn't done since I've had the division). Currently my only option for giving cool nights is in my garage. It's built into the house and although it's not heated, it never freezes - water pipes run through there by design. But it easily could get into the low 40sF. Is that too cold? I'll be ferrying them daily back into the growing room (LEDs. Thanks for your help. I hope I've given enough info.

[raybark]

It is possible for a single growth to bloom, but the bigger the colony, the greater the resources available to expend on reproduction, hence blooming. Here is an article that was published in the AOS Orchids magazine on the subject.

If you’ve had a single growth for a couple of years, your culture is lacking something the plant needs. I expect at least one new growth per year; more in more mature plants. If you can provide details on your culture - medium, watering habits, feeding, light, temperature, etc. - maybe we can help improve that.

Concerning the temperature, in nature, these plants rarely see lower than the upper 40’s, so it sounds like your area might be too cold.

[Masaccio]

Thanks, Ray. Yep, definitely two years. It was small when I received it and I think it has put on a set of good-looking leaves for each year I give it 25PPM nitrogen of your K-lite CaMg with every watering, which is two-three times a week. This one seems to like it on the moist side. Temperatures aren't allowed to go much higher than 77 or 78, as I'm growing miltoniopsis in the same room. I don't manipulate night temps, but the room faces shady north so it naturally drops a few degrees, especially in the cooler months - too cool actually for a phalaenopsis to be happy. I use a small space heater to boost day temps when needed, and a space humidifier that carries RH up to acceptable levels for the miltoniopsis, and so should be acceptable for everything else in there. Water quality is low in TDS. Light comes from a tracklight fixture with a line of closely spaced Cree 120 Watt-Equivalent 40 degree LED spots (3000K, which I prefer over the bluer option). Pics attached of the plant and set-up.





Oh, and for what it's worth, this one is labeled var. North Vietnam. T

[raybark]

Had you mentioned it was small when you got it, I might have withheld my “something’s wrong” comment. If you can grow and bloom other plants under your overall regimen, this should be no exception.

Sometimes immature plants, if potted individually, can be very slow to grow at first. I acquired a single-growth Paph. stonei from a grower who gave up on it after 4 years. I had it for two more before it bloomed. Now it has two growths - still slow growers, but faster than before (although I’m sure KelpMax has helped).

[Masaccio]

Thanks. I appreciate it. The haynaldianum that you see in bloom in the picture has taken two years. It was a single growth, in spike, on arrival. The spike blasted (winter shipping I suppose). But it was a good lesson on having to wait on Paphs to put on some size before expecting bloom. So that was my question about the micranthum. It's not worth bothering to schlep it into resting night temperatures if its not blooming size yet. Last year, it rested naturally in situ. But if flowering depends on significantly lower night temps I'm willing to do that if it's big enough.

[raybark]

I think the plant needs more mass before it'll bloom.

With micranthum, "winter rest" means no fertilizer and brighter light, but not dry. Yes, the rains decrease over winter in their natural habitat, but fog and dew keep the plants lightly moist, so I'd duplicate that at home.

[Masaccio]

Thanks for your help. It all makes sense.