Figuring out Bulbophyllum croceum

May 9, 2024

Croceum is now in a wooden square pot with small grade bark. I sold some cuttings recently so I am down to a couple sprigs. It is now in the full light of the LEDs and I am watering frequently. Since last summer I have been cooling the tent down to 17-18°C at night, so perhaps that will make a difference in the plant’s health.

25 February 2024

This weekend I repotted the Bulb. croceum into a smaller container with some long fiber sphagnum moss, and brought it up to the level of the other plants. It is not directly under the lights, but rather shaded by the large Cattleya above it. The temperatures in the tent are already rising to more than 29°C in the mornings, so I will be watching to see if the leaves begin to drop in the coming weeks.

February 1, 2024

I obtained some cuttings of this plant from a grower in Kentucky several years ago, and managed to get it to bloom the following winter. I had it growing in a shallow basket on large grade orchid bark and perlite mix, with some sphagnum moss draped on top to keep it moist.

Since then, I have struggled to keep it happy enough to bloom again. The number one problem seems to be that it drops its leaves just a few months after growing them. In my quest to figure out the culture for this rare and wonderful plant, I’ve collected some tidbits from a couple of different growers who have had some success with this plant, as well as from an enthusiast who has observed it in the wild.

I sent Mikhail Kujawa a division in April 2023, and he recently posted a video of the blooming plant on his Instagram reels (February 2024). I’m thrilled he’s had success with it! On its culture, he told me: “I’m growing pretty bright and with temps 55 nights and days 68-72F. I never let it dry out […]”

Frankie Handoyo observed this plant in the wild on his frequent orchid hunting adventures which he regularly posts on Instagram. writes: “Bulbophyllum croceum in dark forest of Central Aceh, Sumatra, 1700m asl. Cool growing plant, no direct sunlight, keep good humidity…”

Jeffrey Champion posted a photo of his plant on Facebook, which I found and asked him for cultural help. He wrote: “This is a highish altitude plant from around 1500m that grows close to the ground scrambling through scrub an small bushes. It does ok in full sunlight. So you need cool night time temperatures, plenty of air movement and not too much water. Hope this helps [.]”

All three of these sources have mentioned that this plant is a cool grower, although their descriptions of its light requirements are quite different. So that is where I believe I need to pay the most attention to adjusting my culture.

I moved the plant to the bottom of the tent last year to achieve two goals: one was to decrease the intensity of the light, and two was to reduce temperature. So far, it seems to be working. The leaves are staying longer on the plant and look larger than before. However, the plant did not bloom this year, which makes me wonder if the light was too weak.