Dear Docs - September 16
The pictures this week were absolutely gorgeous. How do I deal with the leaf rot, bud rot and root rot which the rainy weather seems to have brought on?
You seem to have two different problems. Leaf rot and root rot seem to have resulted from the rain, and also from lack of fungicide. The bud rot seems to indicate that you have trips/mites.
To treat the leaf and root rot, use Phyton 27. That fungicide is excellent for root and leaf rot. Use 2 tsps of Phyton per gallon of water.
For the buds, use Newmectin at a ratio of a 1/4 to 1/2 tsp to the same gallon of water as above.
Spray the plants once per week for 4 weeks, after which you can switch to a general insecticide and fungicide such as Caprid and Ridomil. Add 1-2 tsp of Caprid with 1 to 2 tbs of Ridomil to the same gallon of water.
When there is much rain, use the fungicide alone about twice per week.
What is the best 'thing' to grow Phalaenopsis? I have tried sphagnum moss, but I almost lost one due to too much rain. Is the packaged orchid mix suitable?
I believe that what is best depends on your unique situation. If you tend to water a lot in general, then use the mix or use a mixture of charcoal, stones and tree fern bark. That way the water runs out. You would use this method too, if your Phalaenopsis are not covered.
The idea is to have the plant dry as soon as possible after watering or after rain, so any medium that does not hold the water is good if your orchids are not covered.
The sphagnum moss is preferred by commercial growers because it is easier on the water bill, as with the sphagnum moss one doesn't have to water until it is 3/4 dry.
Here's an idea that I find is becoming popular: get a piece of tree fern slab and bore three holes in the form of a triangle to use as a plaque for the orchid. The hole at the top is used to hang the plant from a wire, while the other two holes are wired to tie the plant onto the slab. This method has rescued many a half-dead Phalaenopsis, but you need to water more frequently.
These plaques are excellent for walls.
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.