Cymbidium light requirements

[Ted Byers]

I am rebuilding my indoor garden beginning with a couple new Cymbidium hybrids. The ones I got are impressive: lots of large, fragrant flowers, lots of leaves and pseudobulbs. I haven't looked at the roots, but then I don't want to risk the current blooms by shocking the plant. I was shocked at the scent (which I noticed just walking past the first of the plants) as none of the other Cymbidiums I'd ever seen over the years had ever had a scent. And the colouring is striking, despite a couple spots where the plants were nipped by the -

30 degrees Celcius temperatures outside the night I transported them home. I should have waited until this afternoon to get them as today we had temperatues of +4 degrees Celcius, but ......... the flowers remain as vibrant in colour and as fragrant as when I first saw the plants.

I have never had Cymbidiums before, and the cultivation information I received from two different vendors is contradictory. One says they want medium light, at this latitude (southern Ontario) about 20% shade, with only indirect light, and the other says they want full, direct sun. Which is it?

Also, my few remaining my plants died earlier this year because I was hospitalized for a while (serious infection) and so the neglect was too much for them (all my orchids died during the previous, and longer, hospitalization). But I noticed that the demise of the two Hibiscus was accelerated by mites (but these pests totally ignored the Cyclamen which died of thirst and my African Violets which are the only survivors and in fact look outrageously strong despite the neglect, though they lost their blooms). Are Cymbidium orchids vulnerable to mites, and if so are they likely to be at risk from mites that seem to prefer Hibiscus. I ask because I know many pests will attack only a particular species or genus, while there are a few that are generalized enough to attack anything (like my sister's cats, which don't care what species of plant it is that they're destroying). What treatment would you use to kill mites, when the plants are in either a bedroom or a home office? I have tried to minimize their exposure by having the Cymbidiums at the opposite end of the floor, in a different room, from where the infected plants were.

Thanks in advance for any information you provide.

Cheers

Ted

[K Barrett]

Is it a standard cymbidium or a chinese cym hybrid? Santa Barbara can grow standard cyms under high light, full sun for a few hours but ameliorated by shade or dappled sunlight later in the day. So as high a light as you can manage without burning the leaves. They'll also want a 20 degree day night temperature differential in order to bloom. Chinese cyms I grow alongside the cattleyas.

As to the mites, increasing your humidity and air movement should encourage the mites to move elsewhere.

K Barrett

[Ted Byers]

Thanks.

How would I tell if it is a 'standard' or a Chinese Cymbidium hybrid? They are undoubtedly hybrids, but I don't know anything about Cymbidiums, including the difference between a standard and a Chinese Cymbidium. The pink one is labelled as (Fancy Free X Red Beauty) Debbie's beauty, and the yellow one is labelled as Tracey Reddaway 'Geyserland'. They have 7 and 9 flowers respectively, and the flowers are about 12 to 14 cm across. They are both almost a meter tall, with their respective infloresence being long enough to hold the flowers above the tops of the leaves: when sitting on my desk or on my dresser, this puts the flowers right at nose height. The pseudobulbs are about 4 cm to 5 cm across. Does any of this description help figure out whether they are standards or Chinese?

For the day/night temperature differential, I can see that possibly happening either in spring or fall. How long would such a differential be needed, and how should it be timed relative to when they seem to be growing fastest? Cattleyas I know, and had rebloomed several times before I lost them in my second last hospital stay (oh the joys of failing health). Can I rebloom these Cymbidiums by treating them like my catts? And what about what I've been reading about bright light damaging the flowers? Is temperate zone full sun likely to cause such damage?

Thanks again,

Ted

[Steve]

Hi Ted, Those most certainly are standard Cymbidiums. To get them to bloom well, you'll want to give them bright light, brighter than Cattleyas need. They can take some full sun but mid day sun will burn the leaves especially if they are not used to that much light and especially if the air temperature is high. To bloom their best (or maybe to bloom at all) they will need to experience cool temperatures in the fall to initiate flower spikes. If you are growing indoors, the only reasonable way to accomplish this is to grow them outdoors during the summer and leave them out until the nights have been quite cool. They can actually tolerate temperatures a bit below freezing but they don't need or like it that cold. Don't worry about the flowers and too much light. They will be in bloom during the winter months. Mine tolerate lower light during the long winter (because they have no choice here). I live in NY state and you may actually be farther south than I am, depending on what part of southern Ontario you live in. I can be in either Ottawa or Montreal in under 3 hours from here.

Steve

[Ted Byers]

Hi Steve,

Thanks. I am located about two hours north of Toronto (about the same latitude as the southern end of Georgian Bay, which is about a half hour drive from here).

Based on what you say, I have a couple south facing windows that may be perfect for them during the winter as I can place them so they get full sun all morning, and the indirect light for the rest of the day after lunch. Similarly, I have a flower bed at the front of the house that gets full sun until a little after lunch, and then 80% shade (from a neighbor's tree) for the rest of the day. But I suppose that, in the fall, I ought to look into supplemental lighting if they want more light than cattleyas.

How would I make sure I don't bring in garden pests with the pots in the fall? The mites that attacked my hibiscus are, in fact, the first pests I have ever had in my house in all the time I have been growing houseplants. (And my mother had a better track record in never having had her houseplants attacked by pests, at least since I was a kid many many decades ago). I guess the other concern is whether or not the plant will suffer a shock in the fall once I bring it in, changing from nice days and cool nights to steady 20 degrees Celcius 24-7.

Out of curiousity, how long should I expect the flowers to last? And how often should they be repotted? I know repotting is critical for epiphytes, so the roots can breath, but I recall reading that Cymbidiums are terrestrial so I'd expect they'd be best left alone until they're much too big for their pots. Right?

Thanks again.

Ted

[K Barrett]

Hi Steve,

Thanks. I am located about two hours north of Toronto (about the same latitude as the southern end of Georgian Bay, which is about a half hour drive from here).

Based on what you say, I have a couple south facing windows that may be perfect for them during the winter as I can place them so they get full sun all morning, and the indirect light for the rest of the day after lunch. Similarly, I have a flower bed at the front of the house that gets full sun until a little after lunch, and then 80% shade (from a neighbor's tree) for the rest of the day. But I suppose that, in the fall, I ought to look into supplemental lighting if they want more light than cattleyas.

How would I make sure I don't bring in garden pests with the pots in the fall? The mites that attacked my hibiscus are, in fact, the first pests I have ever had in my house in all the time I have been growing houseplants. (And my mother had a better track record in never having had her houseplants attacked by pests, at least since I was a kid many many decades ago). I guess the other concern is whether or not the plant will suffer a shock in the fall once I bring it in, changing from nice days and cool nights to steady 20 degrees Celcius 24-7.

Out of curiousity, how long should I expect the flowers to last? And how often should they be repotted? I know repotting is critical for epiphytes, so the roots can breath, but I recall reading that Cymbidiums are terrestrial so I'd expect they'd be best left alone until they're much too big for their pots. Right?

Thanks again.

Ted

I do not summer my plants outside, so perhaps you should wait for Steve to answer, but a good drench with an insecticide should encourage pests to move along elsewhere. You can use anything from plain old water and liquid dish detergent (a tsp per gallon should do it) or insecticidal soap to anything you can get at a nursery - whatever your comfort level. Hose down the plant and potting medium and let it stand to drain and dry until you bring it indoors.

Another thing to be careful about is losing the plant's name tag. I understand blue jays and squirrels will tug the tags out of the pots. A good habit is to write 2 tags. Push one tag deep into the pot. In case the first one is lost there's a second buried in the medium.

Standard Cymbidiums are epiphytic and or lithophytic, so they have the same thick roots as a Phalaenopsis. Many people let their Cyms crowd a pot. As always wait for new growths and new roots before repotting. Flowers can last weeks if not months.

K Barrett

[Ted Byers]

Hi K

Thanks. That is great.

Your idea of using a tsp of liquid dish detergent reminded me of a mix my sister's father in law used on his fruit trees. He always had nearly perfect fruit. What he used was your mix of soap and water, but he added a little mouthwash (to disrupt the sex life of bacteria - I don't know if it does this or just kills the bacteria, but it makes for a good story ;-) and a little dry mustard. He claimed the soap gives insects 'the runs' and mustard irritates their mouthparts. I don't know if that is true, but, regardless of whether or not his explanations were true, one can't argue with the fact he always had top quality fruit.

I am now concerned about tree rats, now that you mention them. They are a problem, here, and I have lost hundreds of dollars worth of lily bulbs to the damned things, not to mention vegetables I'd tried to grow (something I've decided to let wait until I can set up a sun room or greenhouse). Fortunately they don't seem to have a taste for Iris (which have flourished for me). Do you know if they have a taste for Cymbidiums? Is there a reliable way to keep them away? I have given up on keeping a vegetable garden in part because of these damned critters. I can't sit on my front porch with a sling shot to shoot any tree rat that comes near. I am sure that if I did, the local SPCA would have a few harsh things to say to me.

Thanks again,

Ted