Question
QUESTION: My cymbidium orchid was repotted today in a bigger pot in orchid bark.  The roots were saturated with water, so I left the plant out of the bark overnight to dry.  It was much dryer today.  The roots appear light beige colored and some are stringy white since their casing was mushy and I removed it.  Some of its leaves are pasty whitish on the underside others are specked with brown spots and the tips are brown.  Will this orchid live and rebloom?

ANSWER: Hello Laura,

You submitted three requests, I'll try to answer you on this one response, if that's okay with you.  

From your description of the condition of the roots on your cymbidium, it is a good thing you decided to repot it now rather than later.  Mushy roots are dead and of no longer any use to the cymbidium and may be cut off.  The hard stringy part you see is actually the root, the part that was mushy is called valamen which has the ability to absorb water and hold it until the root needs it.  By the way, healthy roots will have the velamen feel firm when squeezed.  If there are no or few live roots left, leave some of the stringy roots on the cymbidium, they will help anchor it in the potting mix until new roots can grow.  

Why does the velamen become mushy?  The usual cause is overwatering which keeps the roots constantly wet and slowly drowns it.  All orchid roots require some air to circulate around them and when roots are not exposed to air they die.  Sort of like us humans, we need some water but we need air to survive.  

It is best to allow the potting mix to become barely moist between waterings, this allows air to circulate up through the pot as the water is absorbed by the roots.  

Speaking of potting mixes, cymbidiums need a mix that is fairly loose while also capable of retaining some moisture.  Most cymbidium growers use a mix comprised of bark along with various amounts perlite, coir, charcoal, etc.  But it is okay to use only bark.  

A silvery sheed to the underside of the leaves could be caused by insects, possibly spider mites.  Go to your local garden center and ask for a insecticide recommended for orchids and use it according to directions.  It is best to apply the insecticide three times over a three week period to make sure you get the adults along with any eggs that may hatch after the first application.  

I hope this has helped.  If you have other questions or would like more information about the above, write back and I'll try to answer them.  It is helpful to know where you live so I have an idea of what climate you grow them under.  

Jim Kawasaki
San Jose, Ca.


---------- FOLLOW-UP ----------

QUESTION: I live in the Boston, Massachusetts, area.  One more question, when I repotted the cym I placed the bulbous roots in the bark potting mix completely covered with 2 inches of bark mix.  Is this the proper way to replant so that the root gets air.  Please advise.  Thanks.

Answer
Hi Laura,

If by "compeletely covered with 2 inches of bark mix", you mean the bottom 2 inches of the bulbs, that is okay as the minimum is the bottom inch.  

To ensure air gets to the roots, place it where it will be exposed to some air movement for much of the day.  Also, allow the bark to become almost dry between waterings.  As the water is taken up by the roots along with evaporation, the water will be replaced by air around the roots.  

Living in Boston, Mass. you probably could leave the cymbidium growing in almost full sunlight all day but with just a little shading during mid day.  In the fall, allow it to be exposed to warm days and cool nights (65F + days and 40F's night) for several weeks to let the cym know that it is the start of bloom season.  Be on the lookout for a new growth at the bottom of the bulbs, new spikes will be roundish in shape with a bullet shaped tip.  New growths are usually more flattish with a point.  

Hope this helped answer your questions.  

Jim Kawasaki
San Jose, Ca.