Dear Docs - May 27
I'm an avid gardener with a few orchids, most of which are dendrobiums. I've been told that they should be placed on a high level; however, I do not have this facility and I would like to know if this is causing them not to grow. I give them water — mixed with plant food — once every two weeks. Is this enough? Is there a special potting I should be doing? I am currently using stones.
I am not sure at what level they are presently. However, if ground space is a problem I recommend boring holes in the pots at the top near the rim, then extend with wire and hang. Water or fertiliser every two weeks is not good enough. I would suggest every other day for water and at least twice per week for fertiliser. Again, please consider the area in which you live. If it is extremely hot you might need to water more. For dendrobiums, stones are good for the potting material.
The blooms on my orchids are all distorted. Someone told me I could use dimethoate, but it smells terrible. Could you offer an alternative?
Dimethoate will help. It is extremely good, but it does indeed carry a heavy smell. However, other alternatives include the ever-so- faithful caprid or even better, newmectin. For the dimethoate you would use one to two teaspoons per gallon of water. If you're going to use the caprid, which is a double systemic insecticide, then you would use one teaspoon per gallon of water. If you prefer to use the newmectin, you're required to mix a quarter teaspoon per gallon of water.
Betty Ashley is an avid orchid enthusiast who has spent decades successfully cultivating orchids for herself, as well as for orchid lovers across the island, earning herself the title 'Orchid Doc'. Send your orchid questions and/or concerns to: firstname.lastname@example.org.