What Is High Light/Vanda Light In Foot Candles?

[NiNiDazzle]

Since I had to set up a shelf out side with 50% shade cloth for a single den, I decided he needed some buddies. I'm doing internet research and I can't seem to find what foot candles a high light plant and or Vanda plant would need.

Some sites say that Vanda light is 5000 foot candles. Others say full sun. Full sun here in Texas right now is between 9,000 - 11,000 foot candles and it's not even full summer yet.

I've been seeing sooo many plants that I want, but I don't want to burn them or not give them enough light.

The AOS needs to set it down in writing and then everyone just has to follow the guidelines.

[JLu]

"The AOS needs to set it down in writing and then everyone just has to follow the guidelines."

AOS nor anyone else can give you specific light requirements for a genus because the individual species within the genus have different requirements. Lord only knows what hybrids between then require. It's up to the grower to take some general information and find out what his plant likes best. There ain't specific no recipe for success.

That said...you did not ask about any specific Vanda. Does it have strap leaves, semi-terete leaves, or terete leaves? Vandas generally require light levels above 3000 fc, but the more terete the leaves are the more light they can stand or require. While it is reported that some Vandas can withstand full sun (10-12,000 fc), I have never seen it recommended. The usual suggestions are 3-4000 fc. Once you see how a specific individual plant performs at that level you might be able to tweak the conditions for better performance. Keep in mind that plants are not measuring the light, they just need a certain level of photon exposure to grow well or to "burn". The plant can adjust it's defense mechanism to adjust to different light exposures to some extend, but not infinitely.

Light exposure is really an integral of light level and time of exposure. A 1 sec exposure to 10,000 fc followed by 23 hr 59 min and 59 sec of darkness obviously will not work. Neither will 24 hours of 1000 fc (in this Vanda case). Plants need hours of light exposure and hours of darkness to function. So when someone says a plant should get 4000fc, think of that as a maximum exposure to sun in a normal day. The sun comes up and light levels increase to (in this case) 4000fc and then decrease until dark and then the plant gets several hours of darkness to perform its dark functions. If it comes from near the equator then it gets about 12 hours of light and 12 hours of dark. If you only get 9 hours of light (like me in the winter) the plant can take higher light for those 9 hours, but in summer where I get 15 hours of daylight then the plant needs less peak light than at its home base.

My point is that light exposure is much more than an instantaneous measurement that someone can give you in a recipe book.

[Stitz]

Hi Linda,
As JLu noted, "...individual species within the genus have different requirements." The various species have a wide range of requirements.

Some GEEKS have access to OrchidWiz which might provide useful information for you. Select a representative few Vanda plants in which you have an interest.

--Stitz--

[Greybeard]

You've gotten great advice so far but I'll put in my two cents, for what it's worth. I feel that even though a plant might be high light the maing thing is not to put it in direct intense sunlight, most all of the Orchids I have read about are grown in greenhouses where they have better control. Maybe start a little on the weak side of the light spectrum and then let the plant tell what it wants. Watch it's leaves for signs of problems, watch it's growth, it will let you know if it's needs are met Hope I helped a little

[katrina]

Originally Posted by Greybeard

I feel that even though a plant might be high light the maing thing is not to put it in direct intense sunlight...

Well...now that again depends on the type of orchid. I have a few that are in full sun. They grow in full sun in their native habitat so I acclimated them in the Spring for that full sun (vs the T5 lights in the Winter) and w/in a couple/few weeks they are sitting in direct sun...which includes afternoon hours.

[Greybeard]

Originally Posted by katrina

Well...now that again depends on the type of orchid. I have a few that are in full sun. They grow in full sun in their native habitat so I acclimated them in the Spring for that full sun (vs the T5 lights in the Winter) and w/in a couple/few weeks they are sitting in direct sun...which includes afternoon hours.

I fully agree, I don't have a light meter and can't afford one right now, so I kinda work my plants into the light I have to offer( although right now it would be nice to have just a little sun in Col.) which can get pretty intense. They are all I have and I can't replace them right now so I work on the side of overprotective. I strive to make them happy but I might be a little slow to get there, rest assured I'll give them what they want

[Ray]

Originally Posted by NiNiDazzle

Some sites say that Vanda light is 5000 foot candles. Others say full sun. Full sun here in Texas right now is between 9,000 - 11,000 foot candles and it's not even full summer yet.

I think that the others have handled the "light level" part well, but you know, you're wrong about summer, too. June 21 was the summer solstice - the longest daytime of the year in the northern hemisphere. (I'm sorry, but I couldn't resist a friendly jab)

[NiNiDazzle]

Thanks everyone. Ok, so what I gathered is that Vanda's want around 4000 foot candles up to full sun (10,000 foot candles). I'm one of those by the books kinda gal and it's frustrating when I'm given ranges.

I have only two Vandas right now. An Ascocenda and a Vandachostylis. It's been sitting in full sun since I received it about a month ago. After 1ish, the sun goes beyond my rooftop and it's in shade.


As for the AOS thing, that was tongue in cheek. I know they can't really be more specific.


So would it be somewhat correct if I set my mind to thinking in these terms?

Shade: 500 - 1,000 fc
Low: 1,000 - 2,000 fc
Medium: 2,000 - 3,500 fc
High: 3,500 - 5,000 fc
Vanda: 4,000 - full sun

[NiNiDazzle]

Originally Posted by Ray

I think that the others have handled the "light level" part well, but you know, you're wrong about summer, too. June 21 was the summer solstice - the longest daytime of the year in the northern hemisphere. (I'm sorry, but I couldn't resist a friendly jab)

I guess I wasn't thinking in daylight hours. LOL Here, the hottest months of the year is August and September so I "think" of that as full summer. Temps go up to the 100's and stays there for a week at a time sometimes. That's how I lost my entire orchid collection last year. I wasn't expecting the sun to be sooo much more intense here. They all burnt to death before I even realized it.

[Greybeard]

It looks good to me but as I said I don't have a light meter, I use the shadow method for measuring light levels and I work them into it gradually so as not to burn them I'm old school, try to match culture, let the plant tell me what I'm not giving it and adjust accordingly. Hope I helped a little and good luck with your new Vandas and keep us posted I want to see blooms

[digitalgate]

Originally Posted by NiNiDazzle

I have only two Vandas right now. An Ascocenda and a Vandachostylis. It's been sitting in full sun since I received it about a month ago. After 1ish, the sun goes beyond my rooftop and it's in shade.

Let me differentiate further. Ascocenda depend if it has any terete blood in the parentage, will need around 4500 to 6000. If the terete blood is strong, then just dump it in full sun. However , normally strap leave (including **stylis) is medium light. Nothing above 6500 from 4500 fc. If you are suggesting vandachostylis it is possible for this to handle full sun light.

[jerrymeola]

When I give a lecture I like to say this is one of those ideas about orchids that is both right and wrong.

Light itself is never a problem with orchids but the heat that comes with the light is what kills the chlorophyll in the leaves.

The reason for ranges is that there are a lot of others factors coming into play. For an extreme example I had an entire table of Oncidium out in direct South Florida sun last May at the Redlands International Orchid Show. It was 11,000 foot candles (90 degrees) whereas Oncidium like 2000-3000, but a strong breeze off the lake blowing on the plants kept them perfect all weekend. One hour of stagnant air would have damaged them. It made for a good demonstration when the customers could feel the leaves and reasize there was no heat build-up.

So ranges and generalities are what is a safe medium for the average hobbyist. It is not gospel. There are exceptions to everything.

As to your Vanda. Here are general ranges for various types subject to the actual growing conditions you have.

Strap leaf Vanda 4-7000 This range means anything inside the range. They can flower at 4000 and leaf damage can be avoided up to 7000. This is usually the number given when someone asks for the light requirement for Vanda. I have grown these as an experiment in full 10,000 foot candles over a Florida summer with temps in the 90-100 range. The plant survived and flowered well. The leaves took a beating. After all I wilt in the hot summer sun so why expect more from your plants.

Ascocenda, the term will disappear next year, (the family Ascocentrum is being eliminated and all will be just Vanda next year) are generally lumped with Strap leaf Vanda but can do well on the lower limits of light. They will be a strop leaf Vanda under the new naming classification.

Terete leaf since they are rounder and do not have a flat area on which the heat can build up can take higher levels of sun. The physics of heat is that heat rises and the pointy round leaves of a terete shed the heat.

Vandostylis and Rhyncostylis can flower very low levels of light for the Vandaceous group. I grow these as low as Phalaenopsis 1000 foot candles. Especially when they are young. Leaf spotting occurs in normal Vanda light although they will do well up to 3-4000.

Mokara can take 100% South Florida sun. They are popular here to attach to palm tress without much shade. There are some 30 foot ones attached to the wall of the American Orchid Society building in full sun.

This leads to the second fallacy in "recommendations for light levels for orchids". Usually the range given (4000-7000) is the lowest amount generally needed to flower (4000) and the highest amount is the point where heat damages the leaves (7000). Most commercial growers myself included grow young plants in much lower light then necessary to flower. The are too young to flower so do not need the light, and lower light allows the plant to retain moisture easier. When plants are struggling against heat they slow their growth to conserve moisture. I want them to be growing 100% all the time so Vanda seedlings at 200 foot candles do just fine and grow faster.

[Stitz]

Originally Posted by NiNiDazzle

So would it be somewhat correct if I set my mind to thinking in these terms?

Shade: 500 - 1,000 fc
Low: 1,000 - 2,000 fc
Medium: 2,000 - 3,500 fc
High: 3,500 - 5,000 fc
Vanda: 4,000 - full sun

Linda, Please, identify the Vandaceous species or hybrid in which you have an interest. Many need far more than 4000 fc. For example, Ascocentrum curvifolium is a component of some hybrids. This species needs ~ 2500-3500 fc, according to Baker. Baker suggests up to 6000 fc for Vanda teres.

This critical difference might make the difference between growing a flowering orchid or owning one which never flowers or worse yet, killing one.

It really helps to know your plants before you purchase!



--Stitz--

[NiNiDazzle]

Originally Posted by Stitz

Linda, Please, identify the Vandaceous species or hybrid in which you have an interest. Many need far more than 4000 fc. For example, Ascocentrum curvifolium is a component of some hybrids. This species needs ~ 2500-3500 fc, according to Baker. Baker suggests up to 6000 fc for Vanda teres.

This critical difference might make the difference between growing a flowering orchid or owning one which never flowers or worse yet, killing one.

It really helps to know your plants before you purchase!



--Stitz--

I received these two vandas as part of a potluck. That's why I'm trying to find the right culture for them.

Vandachostylis Colmarie 'Carmela'
Ascf. Cherry Blossom 'Carmela'

[NiNiDazzle]

After reading Jerry's post, he might have hit a point as to why my two Vandas haven't burnt to death. My backyard gets a lot of breeze. The patio area is a U and any wind we get is magnified.

[jerrymeola]

Linda you have two of my favorite plants. The Van. Colmarie is extremely fragrant and the Ascf. Cheery Blossom is a miniature Neo. falcata hybrid, unfortunately this one did not inherit the fragrance of its parent.

Both can grow in lower light levels. I have Colmarie growing from 4000 foot candles down to some for experiments as low as 1000. It does not seem to matter for its growth where in this range it is. They flower in January and then I will see how low a light level is sufficient for flowering. The flowers are petulant inherited from its Rhyncostylis parent. Rhyncostylis can flower in Phalaenopsis light levels so I expect this one will as well. They flower on plants as small as 5 inches high and a leaf spread of about 10 inches. [IMG] http://orchidsamore.com/photo_galler...marie_2737.jpg [/IMG]

The Ascf. Cherry Blossom have just finished blooming in May. They flower on a plant as small as 4 inches high and a leaf spread of only 4 inches. The pot in this photo is a 3 inch pot.
[IMG] http://orchidsamore.com/photo_galler...ossom_5762.jpg [/IMG]

Both plants are excellant choices for those wanting Vanda without our Florida Sun. Both should be capable of flowering indoors in a very bright window.

I do not know why the photos are not posting. The code used to display the photo. If you click on them it works as a link.

[NiNiDazzle]

Thank you Jerry. I did not realize that the ones I had could already be blooming size. The only vandas I usually see are the monster size ones.

hmmm... Now that I know about these mini types that can be grown indoors, hopefully well under lights, that has opened up an entirely new door for me. I can see my husband rolling his eyes at me now.

[JLu]

"Ascocenda, the term will disappear next year, (the family Ascocentrum is being eliminated and all will be just Vanda next year) are generally lumped with Strap leaf Vanda but can do well on the lower limits of light. They will be a strop leaf Vanda under the new naming classification."

If that's true it's the best kept secret in botany. You got a reference for that?

"Vanda seedlings at 200 foot candles do just fine and grow faster"

I seriously doubt that information. Hosta growers plant seedlings in full sun to grow them faster for market. They look terrible but grow faster. It makes sense because plants make food by photosynthesis that is initiated by photons. So it makes no sense to assume that light levels as low as 200 fc are beneficial to plant growth.

[orchids4me]

Very interesting thread good question and excellent answers, thanks j lu for letting us know about the name change coming for next year.
Emmaye

[JLu]

No,no,no.............. I did not say there is a name change for Ascocentrum...Jerry said it and I asked for references because I do not know anything about it and that's unusual.

First someone must properly publish a proposed taxonomic proposal. Then it sits while it is peer reviewed usually for years. Sometimes the proposal becomes acceptable to many peers and some agency such as KEW or IPNI or both finally accept the change and declare it accepted. The Cattleya change was proposed in 2001 and not fully accepted until 2009 and that was a quick one.

I know of no proposal to change Ascocentrum...that's why I asked for a reference.

[kmarch]

Originally Posted by jerrymeola

Ascocenda, the term will disappear next year, (the family Ascocentrum is being eliminated and all will be just Vanda next year) are generally lumped with Strap leaf Vanda but can do well on the lower limits of light. They will be a strop leaf Vanda under the new naming classification.

Can you please provide a source for this info? Thank you.

I have a 7 yr old vanda sanderiana alba that thrives in my bathroom window facing an eastern sun (it gets direct sunlight through the glass pane maybe an hour a day early morning then diffused lighting the rest of the day(New York has a brighter winter sun than summer and I dont know why this is so)...it just likes the hot steam everytime I take a shower because the roots tend towards the tub; so I just water it once a week it flowers every spring and early fall(it likes the cold I suppose)...it seems happy...even if I dont know what incandescence light saturation it gets...I guess I lucked out on this one