Bob, the orchid is species Cattleya labiata, but I don't know the particular variety, as it's one that was given to me by an old family friend, now deceased.
Dina, when they're in the green house, I don't have that problem. But when I put them outside, some days the humidity is too low for them, and the buds dry up. Try putting your potted orchid in a bowl atop a layer if pebbles, which you will keep moist. That will increase the humidity around the plants.
Imagine the rain forest, where they grew.
In regard to fertilizer, I put a time release fertilizer in the pots, then feed them Miracle Grow during the growing season. But...I need to do some research on that, because the blooms on my white orchids are much smaller than they should be.
We get by with a little help from our friends