With Ted Smith
Those of you who were here last week will remember that we spent the entire column talking about moth orchids. As we discovered, moth orchids (Phalaenopsis sp) are a relatively easy houseplant to keep healthy and happy as long as we’re sensitive to a few basic requirements. Today we’re going to address a few final housekeeping details related to the moth orchids.
One critical aspect of moth orchid care that we didn’t get to last week is the issue of re-potting. Orchids only bloom happily when slightly root-bound but should still be re-potted every couple of years. Clay pots are preferred over plastic as they allow the potting medium to dry out more quickly than plastic pots. This is essential to prevent root rot.
Clay pots also offer the advantage of providing a heavy base which can help prevent them from toppling over when a full stem of flowers makes your orchid top heavy. Pots should also be selected to allow for replanting without bending or curling roots yet simultaneously, not leaving too much extra room once they roots have filled the pot.
When purchasing a potting medium for your orchids, be sure to buy specific orchid blends. These may be made up of (in varying proportions) fir bark, sphagnum moss, horticultural charcoal and perlite. These ingredients combine to produce a highly porous medium that allows for rapid drainage. The charcoal is helpful in counteracting the negative effects of the salts found in most commercial orchid foods.
Never use regular potting soil for your orchids. Most orchid roots simply cannot survive in the high moisture environment found in potting soils. Re-potting of orchids is generally best done when they are actively growing, but not in bloom.
When you’re ready to re-pot, the hardest part may be getting your orchid out of its old pot. Since orchid roots tend to cling to the side of their pot, you may need to break the pot in order to get the plant out without breaking any roots. It is important to not damage any of the living tissues of your orchid as any damaged tissues can quickly degenerate and lead to the death of the plant.
Once your orchid is out of its old pot, all residual potting medium must be removed from the roots. A gentle wash in room temperature water may be effective in helping to do this. Once your roots are cleaned, examine them closely. Live roots should be obviously distended and firm. Any soft mushy roots or dry wiry roots are dead and should be removed with a sterilized razor blade. At this time, any dead or dying leaves should also be removed from your orchid.
Now place a layer of a few centimeters of potting mix in the pot. Next, gently settle the orchid into its new home with as little bending or curling of the roots as possible. All that’s left now is to gently fill the pot and all the spaces between the orchid roots with potting medium. When done the pot should be completely filled with potting medium, but not packed in.
Once this is complete, it’s time to thoroughly soak your orchid’s roots and growing medium with tepid water. Never use cold water to water an orchid. I’ve read of people (even professional websites) suggesting the use of ice cubes as a method of slowing watering orchids but that is a potentially deadly idea as tropical orchids have little tolerance for cold.
If you keep your orchid very happy, you may notice tiny infant orchids, “keikis,” growing at the nodes of the main stem. Interestingly, keiki is the Hawaiian word for baby. On rare occasions I’ve also seen them develop on spent flower stalks. You may need to wait anywhere from six months to a year but once your keikis have two or three leaves and roots that are several centimeters in length, they can be removed and potted on their own. A very sharp sterile knife or razor blade can be used to cleanly separate the keikis from their parents.
From here they can be re-potted as per the above instructions and grown out as a brand new orchid. Keep the new orchid well watered, but never wet and mist daily.
Young orchids are very temperature sensitive and appreciate average home temperatures where the nights are a little cooler than the days, but still warm. Within two years your new orchid should be in full bloom and will be an exact clone of its parent.
There are other ways to propagate moth orchids but starting with a keiki is the most reliable. Oddly enough, starting from seed is virtually impossible except in laboratory conditions.
One last consideration when caring for moth orchids is pests. While most orchids are relatively pest-free, when stressed they can succumb to pest colonization. Scale, aphids and mealy bugs are the worst and are best avoided through constant vigilance.
