Of the several thousands who join the ranks of hobby greenhouse gardeners each year, few, I am sure, do so with the intention of making money from their hobby. Yet it is surprising how many gardeners under glass eventually use their talents in this direction.
My first ventures in greenhouse gardening were for the sheer joy of nurturing seedlings to maturity and possessing beauty of form and color available, to my way of thinking, in no other way. Yet it wasn't long before a chance remark of mine opened up the possibility that my greenhouse activities might produce a fair return on my investment of time and money.
A greenhouse bursting with cymbidium and cattleya orchid blossoms one early spring caused me to remark that I had so many flowers I didn't know what to do with them. A friend who heard my comment spoke to a florist who offered to buy all the cut orchids I cared to sell; it was as simple as that! Each spring my greenhouse brims with blossoms and I think that perhaps I should accept the florist's offer. But I keep putting it off I just can't seem to part with any of the flowers, at least not in that way. I'd rather give them to friends.
The point is: there is a ready market for the plant products of anyone who might like to turn his hobby into an income-producing past-time, and not only for orchids. Home greenhouse gardeners often find a market for foliage plants, or for seedlings for outdoor gardens in spring; some specialize in one kind of plant, as African-violets, geraniums, even herbs; others find corsages profitable.
Investigate opportunites, both online and offline, if making some money doing something you love is of interest. Pick a niche and work your interest and the numbers to see if anything fits both criteria.