I think cattleyas and their intergeneric or transgeneric hybrids in general deliver the biggest flowers for the plant size.

However, if you want the absolute biggest in flower size to plant size ratio, nothing can beat the 'ghost orchid' which consists only of roots and flowers. (No leaves or stem.) :)

{{gwi:184304}}Ghost orchid (Dendrophylax lindenii)
http://www.flickr.com/photos/zeodad/2542871261/

This question comes up from time to time and what you really want is what is the best orchid to grow in your conditions in Zone 4 USA?

I do not know!

Do not be lead astray by beautiful pictures of orchid X. Orchid X might be an absolute beast of a plant to grow and flower in zone 4.

Anyway, for what it is worth I'm nominating Tolumnia Hybrids as non space hogs that deliver a lot of flowers relative to the size of the plant.

Tropical philippines, nice pictures. You make a good point - I had not considered the leafless orchids. They probably win out against everything else... out of curiosity, are the flowers of Polyrrhiza lindenii bigger than those of the other leafless orchids?

Arthur, I don't know about the Tolumnia hybrids because I don't have any, but I have Tolumnia hawkesianum and it's very compact, and produces a very long, graceful spike with a nice spray of flowers.

Mike

My vote (Ghost Orchid excepted) goes to Beallaras:

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This'Tahoma Glacier' has 3 pbulbs and another one emerging, in a 4.5" pot. Height of leaves is 12" and maximum spread 10". The flowers were approx. 3.5" wide and lasted five weeks.
Judy

The various clones of Lc. Mini Purple comes to mind. My plants are about 5" tall, if that. Flowers are 2.5 to 3".

Mike,

I don't know if 'Dendrophylax lindenii' (previously known as 'Polyrrhiza lindenii') has bigger flowers than some other leafless orchids as I haven't encountered it.

I live in a tropical climate with only two seasons, dry and wet, so we just hang orchids outside on trees, 365 days a year. Because of this, flower to plant size is usually not a priority. We just choose orchids based on maximum impact: the largest, grandest, most beautiful display of flowers all year round. If this were the only basis for choosing orchids, I think the vandas will easily become the darling of the orchid world. (You can invest on a greenhouse so you can grow all kinds of orchids with no size limitations.)

{{gwi:179490}}
Vanda sanderiana (formerly Euanthe sanderiana)
(Endemic to Mindanao, Philippines. Endangered species. Flowers can grow as big as the size of a saucer or a small plate. Can have multiple flower spikes ranging from 2 to 4 per plant with 6 to 10 saucer-sized flowers per spike or inflorescence.)

Up a few posts i said.... "Do not be lead astray by beautiful pictures of orchid X. Orchid X might be an absolute beast of a plant to grow and flower in zone 4."

In the past, i was lead astray and tried to grow Vanda sanderiana (formerly Euanthe sanderiana). This is zone 9/10 temperature wise, but the humidity outside today is about 40%.

Of course, the plant died after a long lingering slow death.

Gorgeous flower, but i'm now trying to grow a few Vanda Hybrids without that species as a recent relative.

Don't feel bad Arthur, I've killed every Tolumnia I ever had. One lingered for 4 years until it got Kev'd.

Jane

Very small plant with nice size flowers

B. Little Stars
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Forget Catts. or any other alliance other than Angraecoids. Check out some google images for: aerangis punctata, splendida, and fastuosa. Angraecum elephantinum, leonis, magdalenae, florulentum. Aeranthes grandiflora, caudata. There are many more.

Arthurm,

Don't be discouraged growing tropical vandas like vanda sanderiana or its hybrids. They are one of the most beautiful orchids around. Limiting yourself exclusively to the
cold-tolerant vanda coerulea and its hybrids seriously narrows down your choices to mostly mediocre-looking tessellated vandas. (Tessellation is a dominant trait usually passed on by the cold-tolerant vanda coerulea to its progeny.)

Also, even if your vanda hybrids don't have vanda sanderiana in their genes or lineage, there is still no guarantee they will survive in your zone 9-10 area if you don't get things right, be they cold-tolerant or not. They are still vandas after all, and vandas are 'sun' and 'humidity' worshippers. They may differ in how much sun or how low a temperature they can tolerate, but they are unanimous in one thing: they like humidity and lots of it.

Here's one most important thing about vandas according to this Orchids Asia website (which could prove to be a challenge to those living in four season climates [like yours], 'frost-free' or not):

Humidity should not be less than 30% at night and 80% during day time. The plants should be watered 2-3 times a day and should not be allowed to dry up during hot climate.

Source: http://www.orchidsasia.com/project03.htm

Here is how they achieve this humidity in their open shade houses in their tropical two season (wet and dry) climates:
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They employ shade nets (30%-50%) depending on type of orchid to ensure maximum blooming for their orchid cut flower industry.

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They employ wood shavings bed at the bottom to keep the humidity high.

More references here from the same website (Orchid Asia):
http://www.orchidsasia.com/vanda.htm
http://www.orchidsasia.com/vanda/vanda1.htm
http://www.orchidsasia.com/vanda/vanda2.htm
http://www.orchidsasia.com/project03.htm
http://www.orchidsasia.com/project01.htm
http://www.orchidsasia.com/consult01.htm

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Mokara culture

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Mokara cutflower industry

If you have a four-season climate which occassionally experiences frosts, then an open shade house like that shown above (applicable for tropical climates) may be insufficient. A more enclosed greenhouse may be necessary to avoid temperature drops and humidity drops that can adversely affect vanda growth and flowering.

Whether an enclosed greenhouse with heating and humidity control is feasible or not depends on how you see it and how much you are willing to spend.

Even apples can grow and fruit in tropical climates like Indonesia. They just can't compete though due to cheap imports from China and other countries like yours which have climates more conducive to apple growing. In the same way, you will never be able to compete with vanda growers from tropical Asian countries, but you will still be able to grow them anyway in your greenhouse (if you are willing to spend for it).

tropical

tropical, I am having trouble seeing some of the pictures you have posted - is anyone else having this problem? The captions you have written are intriguing, so I wish I could see the pictures.

treehaus, You're having trouble seeing some of the pictures? I can't see them at all!

I'm getting the X in a box thing. I would love to see the pictures too!!
Pat....

I'm with Breezy here. Angraecums didieri, elephantinum, and compactum have amazing plant to flower size ratios. They are minis (my didierii and compactum are all of a few inches tall and blooming size). My didierii can produce a bloom almost as big as the plant itself, if grown well enough (which I haven't been doing lately).

Oh, and Schoenorchis fragrans, another mini. Though the individual flowers are absolutely tiny, a mature plant will produce a large cluster of them that can almost completely occlude the whole plant.

treehaus, stitzelweller and pcan-z9,

You usually get the 'X' in a box syndrome if there are too many visitors accessing/viewing the photo(s).

Here's a trick to reload the 'X' in a box photos:

If you are using Microsoft Internet explorer, right click on the 'X' and then click on 'Show Picture'. The picture should get displayed. If you still get an 'X', just repeat the 'right click' trick until such time it displays the photo. (If it doesn't display after right-clicking several times, try again during non-peak hours. The server could be busy.)

tropical

Breezy is just a wee bit biased though I don't fault his selections. Only problem is angs basically only come in white/green.

A lot of course depends on where you will be growing them and personaly preferences. Haraella odorata has a very nice flower to foliage ratio as does Slc Firelighter, for example.

Hi, Tropical,

Your pix have never shown up for me, even at 4:00 a.m., CDT. When that little no picture icon shows up, I've never seen the picture, be it Mac or Windows.

Would love to see them.

Whitecat8

I use Mozilla Firefox, and after right-clicking and choosing "view image", the photos are visible. It's currently 8:45 am, Central Standard Time. Perhaps reloading the page, and then doing the right-click, view image thing would work... or, you could try right-clicking and opening the pictures in a new tab. That sometimes works for me when I run into a brick wall... other than that, I'm afraid I can't help.

I only wish I had the humidity to grow Vandas... the bloom colors are incredible... and even the plants, themselves, have a nice shape! But, I'm in a 4 season climate with dry air half the time... no Vandas for me!

Whitecat8,

Try the 'right-click' trick I mentioned above. It should work. If not, repeat the right-click trick until the photo is displayed.

Alternately, you can click on the reference links I've included. They are from Orchid Asia, the website where the photos I attached are stored.

tropical

Hi Tropical, I've just returned from a large orchid show where the largest number by far of orchids on display were Cymbidiums. Hundreds of them.

How many Vandas? Half a dozen, poor examples when compared with those grown in tropical lowland climates.

I'm still hopeful of getting some decent flowers on the cooling growing types I'm trialling, But. i know that they will be inferior to the dinner plates types that you see in orchid magazines.

Interesting that i got seduced all those years ago by a photo in an English Orchid Book....Orchids for everyone. I suppose i could break the budget and heat one of my glasshouses to 16C at night. Instal some misters. Fix the shading and turf out all the current inhabitants......