Growing beautiful orchids on trees is an easy and rewarding thing to do. Of course it really helps if you live in a famous orchid growing region (east side of the Big Island of Hawaii) where the temperature and humidity are so perfect that your orchids can grow on pure neglect! But please read on as I will also include a link to growing orchids on trees for people who live in other states.
For the past 13 years I have been growing all kinds of orchids on the native Hawaiian Ohia trees which surround our home. (Read how we saved hundreds of Ohia trees on our Big Island rainforest property.)
First carefully take your orchid plant out of its container or pot. Gently loosen the roots and shake off most of the potting soil. Next, look at the tree you have in mind for where you want to place your orchid plant. Try to position the plant where you will be able to see and enjoy it in bloom. The orchid flower blooms will last for weeks! It's nice if you have a crook where the branch comes out of the tree trunk so the orchid plant can nestle in it. If not, you can tie it directly to the side of the trunk securing the orchid plant to the tree with string. Make sure the string is tied snugly around the the plant and secured to the tree so it is not loose and could move in a breeze or fall, but not so tight that the string cuts into the plant. It is better to use natural string or twine so it bio-degrades naturally after some time. You can also add spaghum moss or a piece of hapuu fern bark if you live in a dry area. I did this at first but it rained so much here that it rotted the orchid plant roots and also attracted lots of ants that made a nest in it.
Observe where the direct sunlight hits your tree during the day. Do not place orchid plants in places with lots of full sun unless it is the type of orchid that likes a lot of sunlight. Some of my plants shriveled up and died with the leaves burning and turning black. Most orchid plants do best in areas with filtered sun light or partial shade.
It is important in the beginning to spray your orchids with water (using a water misting bottle) completely everyday so it does not dry out, unless it is raining every day.
Every few months you can spray an orchid fertilizer over the whole orchid plant, according to the manufacturer's directions.
I have over a dozen different varieties of orchids in different sizes, colors, and fragrances, that bloom at different times throughout the year. Cattaleyas, oncidiums, eppidendrums, miltonia, dendrobium, dendrobium nobile, and some others that I forgot the name for.
The top photograph is of a cattaleya orchid plant, and the bottom photograph is of a "chocolate" orchid or brown oncidium orchids, both of these plants are a few years old and have been doing well in our yard.
Most orchids are epiphytic. Epiphytes which literally means "upon the leaf" are sometimes commonly known as "air plants". This means that they grow on trees or other plants and get their moisture from the air. Nutrients are obtained from rain carrying decaying matter over the roots.