Antonio De Gannes gave a very informative lecture on growing Dendrobiums, which is the second largest group of orchids with over 1200 species. He advised that selecting plants to grow should be based on the parentage of particular plant hybrids with emphasis on selecting those with suitable intermediate to hot growing temperatures and elevation where they are found in the wild. We should select plants with warm growing parents and found at sea level. 

He grows his dendrobiums in bright light with good air movement. Do not water plants after 4 pm as this promotes fungal problems. His potting media is broken red clay blocks and charcoal. He prefers to stay away from using coconut shell as it breaks down after 1 - 1.5 years at which point you need to re-pot on time or you can lose your plant. Two key indicators that your dendrobiums are doing well are each sequential growth being larger and green root tips. His fertilizer of choice is Nutrex 20-20-20 at ¼- ½ tea spoon per gallon twice per week, applied during the cooler parts of the day.