Ponerorchis graminifolia bud blast

[Nlamr]

Curious if anyone would have thoughts or suggestions... My graminifolia grows beautifully, and this year had twice as many buds as last year but both last year and this year the buds get almost ready to burst, then stall and never open. They don't suddenly all drop at once, it is gradual. Because this is the second year in a row that this has happened I am curious if I am missing something in their culture rather than external factors. They are potted in kanuma, and I keep the media moist, distilled water only. I do use MSU fertilizer but it is very minimal, I have actually only fertilized them once all summer at 1/4 the recommended dosage and that was previous to the spikes forming. They have been kept outside since Spring (I keep them in my fridge over winter because they will not survive my Winters). They are on an East facing, covered porch and the temperatures have stuck around 60-70° at night and 70-85° during the day for the last 2 months. They essentially get the same care as my Habineria radiatas and those bloomed beautifully last year and I have no reason to believe they won't this year as well based on the health of the plants. Any thoughts are greatly appreciated!

[Subrosa]

I keep mine moist during the winter, but decidedly wet during the growing season. Where are you located in the US? They winter over in the ground for me in the Appalachians of PA, zone 6B.

[Nlamr]

I'm in Western New York, zone 5a so not far off, maybe I will get another one and experiment with that! I do leave moisture in the pot when I store it (kanuma is great at maintaining moisture but keeping things airy as well), perhaps some sphagnum moss in the pot will hold more moisture. Thank you I appreciate your input!

[Subrosa]

My in ground plant has formed a nice clump over the past couple years, so you may well find you have an extra tuber to experiment with. Fwiw the plant is listed as being zone 6 hardy, so if you put it in the ground against a south facing foundation wall and mulch it well, you might find you can keep it out year round in 5A.

[stonedragonfarms]

I grow them potted as well, but like Subrosa, I too keep them damp over the dormant period. In active growth, they sit in a saucer of water which I keep topped off. I repot mine yearly, at the beginning of March, they are in equal parts of pumice & chopped coir fibre. I fertilize mine heavily--ie I give them a top dressing of Nutricote time release when I see the first sprouts break in spring, and they get additional fertilizer [K-Lite] about every 10 days from mid April-mid October. I'd wonder if the bud loss that you are seeing is a result of either a calcium or magnesium deficiency. The only other thing that immediately comes to mind would be substantial swings in relative humidity; any chance they are getting a substantial humidity drop [in particular at night]?