AboutWayne King Expertise Any question about orchid culture. I have thirty+ yrs of growing experience,president 2x of our local Orchid Growers Guild,held a position in most all other offices associated with the Guild at one time or another. Head of Orchid judging team for local club meetings and some shows. Member of two Orchid Socities and local Rep.for Mid America Orchid Congress for several yrs.I have in my collection about 800 Orchid plants of all types.
Experience
Past/Present clients Previously an expert on expertcentral.com.
Question I have a phal that is not happy. It was in flower when I bought it 2 months ago, and it appeared to be growing sideways in its pot with growing around the plant rather than on either side – but the flowers were so pretty. It was in a clear pot which was filled with fat green roots.
When the flowers faded shortly after bringing it home, I decided to repot it and it was then that I noticed that the lower part of the stem was dried up and black with a live part underneath it from which all the fat green roots came from. Above the dead black section there were four green shortish roots (which had brown soggy tips) and two aerial roots. I am wondering if the pot may have been knocked over at some time in the shop and the plant and its bark shoved back into the pot.
I cut off the black dead section (which included most of the roots and the flower spike trimmed the tips from the remaining roots and trimmed one of the aerial roots so I could tuck it into the pot, and repotted it back into its pot with some chopped Styrofoam packing and fresh orchid potting mix.
The leaves became a bit limp and have remained like that until this last week when it started growing a new leaf. The 5 leaves (which are about 7” x 3.5”) became quite limp and floppy with the lowest leaf starting to yellow.
I decided to check the roots and found that the base was again black (or maybe I didn’t cut it all off the first time) and the lowest root, although looking fat green and healthy, was broken and dry where it joined the black stem. So, heart in mouth, I’ve cut the stem again back into live (healthy?) tissue, removing the damaged root. There is still some black on the outer stem, around this live tissue. I’ve also cut off the leaf which was yellowing to hopefully reduce the load on the roots.
At the moment, I have this poor little guy soaking its base and remaining roots in 3% hydrogen peroxide. I will then powder it with cinnamon.
I’m wondering if this dead black stem could be damage or disease and just how to treat it or stop it from spreading. Should I pot it back into its pot with the Styrofoam and bark or put it into a bag with sphagnum moss where I can keep an eye on it while it hopefully grows more roots?
I have other phals which are flowering, throwing up new spikes growing new leaves and all are very happy although some of them are growing roots out through the bottom of the pots. I’m not sure what to do about repotting them while they are so busy as these wayward roots will have to be sacrificed to get the plants out of their pots.
I really appreciate your help
Carol
Answer Carol, thanks for your questions. Your first question concerns "growing sideways". By that I assume you are referring to the flower spike. Flower spikes are phototropic, meaning they tend to grow toward the light. If the light is mostly concentrated lower on the plant, the flower spike will not grow upright. Further, if the plant is not kept in the same position as the flower spike emerges, the spike can become very confused because at one time the light is coming from one dirction releative to the spike and, at another time, from another direction. This will result in a twisted flower spike. Always try to orient the plant so the light is mainly from overhead. Secondly, try not to move the plant while the flower spike is emerging. If you must move it, be sure to put it back with the emerging flower spike feacing the same direction.
Always repot orchids following the bloom cycle. Do not allow the roots (ie potting mix) to remain wet. It must dry out between waterings so check the potting mix before watering. The greatest cause of root rot is lack of air movement to the roots. When a potting mix remains wet, the mix decomposes restricting the flow of air to the roots. One function of repotting is to check the root condition. Orchid roots consit of two parts: a central root fiber used to carry nutrients to the plant parts and an outer thick covering which stores water and nutrients and makes them available for conduction by the central root fiber. When the outer root covering (called the velamin) in damaged it collapses (becomes mushy) and can no longer store nutrients that can be made available for plant growth and flowering. A healthy roots has a healthy velamin which is firm and turns green when wet.
Do not cut the tips from healthy roots. You will notice that growing roots have a green tip. Most root growth occurs from the root tip. When you cut a healthy root you introduce the potential for infection of the root. If the velamin has collapsed, it is okay to remove that portion of the root that has collapsed.
Always try to retain as many roots intact as possible. That might mean sacrificing the pot to extract the roots without damaging them when you unpot a plant. Remember, the more healthy roots you have when you repot, the better. You also may remove a leaf if there is an aerial root above it so you can insert the root into the potting mix. Always soak the good roots prior to repotting as it make them less brittle. I like to rotate the pot as I insert the roots into a pot so the roots can follow the inner walls of the pot and be less inclined to break.
