I have a pair of cattleyas that have developed sheaths but show no signs of having any buds inside.

-one is a large mature cattleya hybrid that was shipped to me with two growths in sheath--the larger of the two new growths did go ahead and bloom, but the second growth doesn't look like it has any buds developing inside the sheath.

-the second is a Cattleya labiata seedling which is still pretty small. I didn't expect it to come close to blooming for a while yet (I think it's 4 years old at this point) but, lo and behold, a new growth developed a sheath--but again, it doesn't show any signs of actually blooming.

These plants are grown outside in Los Angeles under shade cloth. They're the only 'proper' cattleyas I have, but the Encyclias and brassavola nodosa hybrids I grow them with grow and bloom like crazy, so I think they're getting enough light, water, and food.


So what might cause sheath formation but no buds? I wonder if it's possible that they're not getting enough of a drop in temperature at night? It's pretty hot here during the summer. Or could something else be going on? I'd say the C. labiata seedling is just too young, but if that's the case then why is the mature Cattleyanot blooming from the second growth?