August brings us more warm weather, maybe even warmer than July. If you have noticed, our orchids are really growing fast. I hope we are all taking advantage of the long days to water and fertilize our orchids.
It is also prime time for repotting orchids. If you have not done it for two or more years, you are asking for problems. Old potting media breaks down and often becomes soft and water logged. Salts tend to build up if you fertilize a lot. The pH of the media normally becomes acid (low pH) in time. Old roots often die and begin to rot and sometimes there is no air space in the media when they are taken up by roots. All these factors contribute to your media “crashing”. Once this happens your root system and orchid can possibly die.
Watch for initiating roots, this tells you that it is the best time for repotting. After repotting let the orchid dry for a few days, to let the damaged tissues dry and heal. Resist the urge to water right away, this often leads to rotted roots and possibly the loss of the whole orchid. When repotting, inspect the root system carefully. Remove old soft media and dead roots. If the root falls apart when you tug on it, it is probably dead.
On sympodial growth orchids (Cattleya, Dendrobium, Oncidinae, Grammatophyllum, etc), find the lead growths and trace back at least two more growths. Normally three bulb divisions will have minimal set back and could flower on the next growth. Pot into the smallest pot possible and fill firmly with your favorite potting medium. Place the oldest bulb against the pot edge, allowing extra space for the front lead to grow.
It is always a good idea to stake the orchid so that it is firmly anchored into the pot and does not move. If the orchid is wobbly, it will take longer for it to reestablish.
For monopodial orchids (Vanda, Phalaenopsis, Rhynchostylis, Renanthera, etc.), the orchid can be topped if you have a minimum of three good new roots. Set it down deep into a new pot and fill with the appropriate media. The bottom or old part of the orchid can be kept, as it often will send out a new growth.
The Windward Orchid Society meets at 7:30 p.m. on the first Wednesday of every month at the King Intermediate School Cafeteria, located at 46-155 Kamehameha Hwy. in Kaneohe.
Become a member
Join the Windward Orchid Society to help promote, educate and show an appreciation of one of the most beautiful and exotic of all plants. The Orchid.