Daryl Venable on Tolumnia - DVOS September 2018
 

Daryl Venable of Tezula Plants spoke to the Desert Valley Orchid Society Thursday, September 20, 2018, on Tolumnia, his specialty. I was trying to find a way to get the images from his computer to our projector, and unfortunately missed a lot of the talk. What follows is the small amount I heard and remembered while fiddling with cables.

As a result of my distraction, it is very possible I introduced errors into what follows. Those are my errors, and not Daryl's. If people who were there correct me I will edit this and update the notes. I added a few of my observations [in brackets like this.]

Daryl's family moved from the Eastern Cape, Republic of South Africa, to the Miami region when he was 19. He had grown many African orchids, but fell in love with Tolumnias. They now are the main thing he grows.

He breeds Tolumnias. He sells his seedlings, and also mericlones. He sends his seed to Thailand for flasking, then re-imports them when large enough. He also imports small mericlones.

The first thing he talked about was air circulation. He said a stiff breeze in the greenhouse is, by far, the most important factor in growing Tolumnias.

They need very good air circulation. He realized this when he visited a master Tolumnia grower, and noticed all the plants' leaves were moving constantly in the very strong wind from many big fans. This kind of air movement cuts down on infections. He has many fans in each greenhouse. He said anybody growing Tolumnias needs to have big, strong fans blowing on their plants.

Tolumnias do better with roots attached to something, rather than loose in the air. He prefers to mount his plants. They can be grown in small clay pots. They can be grown bare-root in these pots, but they do better with tightly packed medium, so they don't move at all. The medium needs to drain rapidly, and provide plenty of air at the roots.

He puts imported seedlings and mericlones bare-root into tiny net pots, and sells them. This is an acceptable short-term solution for growing them, but he would not grow them like this long-term. The plants he keeps for breeding he mounts very firmly on cedar, which lasts the longest among other kinds of wood in humidity. He can't use cork for mounts, because a tiny local beetle destroys it quickly. [He talked about going to a lumberyard for cedar scraps in bulk, but I have found I can buy a 6' / 1.8 meter tall x 6" / 15cm wide cedar fence plank at Home Depot for $3 and cut it up with a hacksaw. I don't have 50,000+ plants like he has.]

If you don't want to mount them, they must be very firmly anchored in the medium, or they will not root and take off growing.

They must be very firmly attached to the mount, with no possibility of motion, or they will not root onto it. Most ties of nylon, cotton or similar will damage the plant if tied tightly enough.

He prefers to use strands of nylon pantyhose to tie the plants. He cuts off the feet and top, rolls the leg section tightly into a donut, then cuts the donut into 1" or 1/2" sections. Then he unrolls these. They are usually much longer than needed, especially because they stretch, so he cuts them down to length. He uses them around the entire base of the plant to attach it firmly. He doesn't take off the pantyhose tie as plants grow; soon it is buried and can't be seen.

He mounts new growth facing the mount wood, not away, so it attaches more firmly to the wood. He thinks this is very important for establishing plants on mounts.

They need lots of sunshine to bloom, but they will burn with too much. If an otherwise healthy plant is not blooming, he recommends giving it more light. Lack of sufficient water makes them more likely to burn in the necessary bright light. He grows under part shade in Florida.

[Here in Arizona they tolerate direct morning summer sun through a window if well-watered. This is far brighter than sun in most other parts of the US and Europe. I don't have a spot with more than 4-5 hours of morning sun, so I haven't tried that, but I suspect full sun all day through a window would be fine, if a fan were on the plants and they had enough water.]

They are drenched in dew almost every night in habitat. Then, they dry within a few hours of sunrise. They need a lot more water than most people realize. After air circulation, this is the most important factor in growing them.

In humid south Florida, south of Miami, he often waters his mounted plants three times a day. Because of his high humidity, he waters so they are dry before 11 am, or he is worried about bacterial and fungal rots. Many are seashore plants, and they don't mind water high in dissolved minerals. Save the reverse osmosis water for other plants.

[In my Phoenix sunroom, with 40%-60% relative humidity, I submerge my plants in water overnight several times a week or they shrivel. In very humid areas this would quickly rot the plants. Growers will need to figure out how to balance their humidity with the plants' requirement for plenty of water and air circulation.]

Mealybug and scale attack is usually first noticed when plants develop an unusual, and characteristic, green "rainbow" look to them. The insects hide in plant crevices. They can be found by gently spreading leaves apart. For small infestations brushing and dish soap solution can be used. For larger problems pesticides are used.

Southern Florida growers have to deal with pests and diseases resistant to a lot of chemicals. They can no longer use Orthene / acephate, nor Merit / imidacloprid, because their scale and mealybugs are fully resistant to them. He mentioned two expensive to supremely expensive insecticides he uses on recommendation from a pesticide expert. [I had never heard of them, and I don't remember them, since I wasn't taking my usual notes.]

Florida has a strain of bacterial genus Erwinia which kills Tolumnias within 24 hours of the first signs, turning the plants to brown mush. This bacterium is still susceptible to Physan-20, but it must be applied instantly when the infection is noticed. He reiterated the best way to prevent diseases is with very high air circulation. [He struggles with very high humidity year round. In my lower humidity I don't have any infection problems.]

That's all I heard. I didn't hear him talk about fertilizing, temperature nor humidity. His humidity is very high all year. [I've been to places where Tolumnias live, and they don't always have super-high humidity. None of them experiences frost in habitat. I have observed they don't mind temperatures all the way down to near freezing, so long as they don't turn to ice. Mine grow very much faster as temperatures rise.]

After the meeting, Darryl told me Oncidiums are relatively unstable in mericloning, and meristems for propagation should only be taken from divisions of the original plant, not from mericlones. He said the Thai firm Jairak is careful about this, so their mericloned plants cost a little more. He buys from Jairak. Other Thai firms mericlone the plants they buy from Jairak, then mericlone those mericlones, then mericlone those mericlones... and sell them into worldwide commerce. Very quickly the mericlones mutate into things that look completely different. He said Tolumnia Snow White has become the poster child for this: It is supposed to be white, but a great many mericlones sold as Snow White bloom pink.

If you like Tolumnia Jairak Flyer 'Corona', buy it quickly, because mericlones no longer seem available!

Thanks

Wow thank you!

All the Tolumnias I have seen have been sold bare root, sometimes in a tiny net pot or in a small plastic vanda pot. I'm not sure how to tightly pack in a way and medium that would still allow ample air. Would larger chunks of cork or bark be appropriate?

FWIW this is how I pot mine. I use small bark and clay pots. I pot them up and if needed use a rhizome clip. They root in pretty fast. Here in Indiana, I water them every other day in the warmer months and less in the winter. They are under Sun-Blaster LEDs and they are pretty red. My older ones bloom reliably and my younger ones are fast approaching blooming size. I have an overhead fan running on high and intermediate temps. I have never had any rot and they root like crazy. I fertilize when I think of it.

Clay pots and small bark I have. I'm using T5HO right now, are the LEDs nice?

I am frankly delighted to see some cooler temps just so I can take a break from watering. But now I'm entering the danger zone...still don't have the knack of winter watering.

I'm assuming it's a snug fit in the clay pot and the roots then grow out? I don't want to overpot.

I use 2.5- 3" pots. I put onion net in the bottom to hold the bark. Then I just pot them up.

Your light question:
I use Sunblaster LEDs. (This is a sore OB subject). I like them a lot. They run cool, no heat build up. My high light orchids, Dialalia,Catts, encyclias, bloom under them. They are relatively inexpensive and my husband assures me also cheap to run. Also, they are white not purple.

They grow well mounted or in pots so long as they have lots of air circulation, lots of water, lots of air at the roots and dry out rapidly.

I think the main point regarding potting or mounting is they need to be firmly anchored, and not moving at all, to become established and root into whatever home you provide.

Something that needs to be watered three times a day in Miami is not something I would put into large bark unless I had an automatic watering system.

Those tolumnias I just posted were from Daryl.

I have a terrible time keeping my mounts watered. Going forward, no more mounts for me. Clay is my second choice. But, a wire tie or rhizome clip is a good method to secure them in their pots.

I love the look and the idea of duplicating nature with mounts, but realistically I can't keep up with the water requirements. It's going to be pots. Do I need to worry about clay pots sucking moisture away from the bark? I only have 2 orchids currently in clay, and what I have done is keep part of the clay in water (but making sure the water doesn't reach up to the roots of the plant or potting media) so that the clay stays somewhat damp without anything rotting. Outdoors I much prefer clay to plastic but that's all summer plantings.

To go off topic, does a strip of SunBlaster led lights just light a single row of plants?

Back on topic...tolumnias are such feisty little spiky guys. I've decided I'm not a big fan of oncidiums but tolumnias I like!

Mine are getting ready to bloom. I'll posts pictures. I don't have any problem with clay and bark. OW plants in clay also. You really can't over water that way. My oncidiums are in a moss mix in clay, it works for me and I wish I had never mounted the first plant for exactly your reasons.

OK. They're potted in 1 1/2 and 2" clay pots, in small bark and perlite, and clipped in place. I have no idea why or how, but I had 2" clay pot clips in my array of supplies. They are now sitting in front of a fan under T5HO. Our local hydro store owner is not a fan of LEDs and doesn't carry much in that line. But the T5HO generate so much heat!

This thread is immensely helpful, as I really had no idea they weren't supposed to stay bareroot. I did have two that came potted with what turned out to be a generous two pieces of bark per pot. What I really had in mind long term was to pot them all together in a shallow pan, so that there would be a mix of bloom and it would just be a little different from my usual one plant one pot approach.

Those T5s I had were SO hot! In those tiny pots and small bark, you'll have to water almost daily or at least every other day. They'll not be too wet in that set up. Keep us posted.

I have read and re-read this numerous times. This part confuses me. He waters them three times a day, but has them dry off by 11:00 a.m.? I have mine on a timed mister, 45 seconds, at 8:00, 11:00, and 14:00. Was thinking of adding one more a a few hours later. Wrong way to go?

Mine, mounted on a cedar slab, were out on my deck in southeast NC, about 1 mile from the ocean and 50 feet or so from the intracoastal waterway. They were in nearly full sun and were watered every one or two days, and have done well. I'm sure they'd do better if watered more often, but what am I, a slave to my plants? (Well...yes, but not nearly as much as in the past.)

Remember Tolumnia species are mostly Caribbean. The sea coast species are wet with dew all night, and wet during the day when it rains - which is not necessarily all that often, depending on the island. However, there is usually an on-shore breeze stiff enough to blow off a hat that isn't fastened securely. The highland species get less dew but still some. Miami is extremely humid all the time, and doesn't have that much breeze. There are a lot of fungus problems with all kids of plants in the landscape, all the time.

Most of us have less relative humidity and our plants dry out faster than they would in Miami. I haven't had any rot trouble with Tolumnias, even when I was soaking them overnight 2-3 times a week.

I have about 20 Tolumnia in my collection, the majority of them came either from Daryl or from the bulk group orders that he sometimes offers when importing plants. I have about a third of my plants mounted, the rest were simply tied into 2" clay pots using a bit of twist tie around the base of the plant, then out through the drain hole of the pot--the majority of these rooted extremely quickly into/onto the pots.
Mounted plants have been more trial and error; I prefer to mount on cork or tree fern, but have noticed the best results when whatever mount used is more "branch like" rather than a traditional raft-shaped mount--I'm guessing that a mount with larger surface area=less air flow in the root zone, so over the past couple years have moved to narrower and narrower mounts.
I don't have any of my collection in the greenhouse, as I maintain temps there in the cold & alpine range; but under T5HO I'm running about 50% rh; I mist plants 2x a day, usually about 6am and again about 9pm [1 hour before lights on and an hour before lights out]; I also water plants 2x a week [they get fertilized during these waterings]; the difference between a misting and a watering being the duration of water on the plant--when they're misted, it's 3-5 seconds of directed water [enough to wet down the mounts/pots and see the roots go bright green]. When watering, they get an initial 1 minute spray of room temperature water, a 2-3 minute pause, then another 30 second spray [or in the case of potted plants 6-8oz container pour-over] of fertilizer solution. I usually catch the fertilized runoff water from my mounted plants and use it on my agapanthus pots outside.
How's everybody else under lights growing?

Differently. Mine are in clay pots with small bark. They're close enough to the lights to be pretty red. They get watered every 4 days in the winter. Some fertilizer... A pinch to a two or three gallon container. Some sit on a humidity tray, some don't. My temps 64-77 ( low to high) today 70f. Humidity 57-69% (low to high). No misting. Everyone with any size is blooming.

That would be nice to see.

I've posted...

I'm interested in trying my hand at Tolumnias and have a specific scenario in mind. Perhaps someone here can tell me if this is a good idea.

I have an indoor fountain in a SE corner that can receive good Easterly light in Spring/Summer that I can control, and also a wedge of direct but filtered bright SW sun I can control.

There is currently a large square plexiglass sheet under the fountain to protect my bamboo flooring from light splashing and a light bulb went off tonight that I have orchid real estate I have not been exploiting!:lol:

I keep my humidity around 50% and temps into low 60's high 50's at night, low 70's in the day for Winter. Summer will def bring higher temps and open windows.

Would these conditions be suitable for Tolumnia (I would probably need overhead light in Winter now), and if so, what would be the proper mounting material to have them standing clustered around the base of the fountain? They will get some water spray - nothing overwhelming - but in Winter I'm hard pressed for the fan/drying issue. I do have forced air heat which tends to circulate air somewhat and dry things out and I have managed to keep humidity up artificially.

I wanted to mount orchids on a branch next to the fountain originally months back but had not seen Tolumnia. Now I like the idea of a semi circle around the fountain's base better. My Phals, Cattleya, Oncidium, Zygo are all doing fine in the same area so am betting Tolumnia might also do well? Any thoughts are appreciated. This forum is THE BEST!

Mine like a lot of light, and to dry completely before watering. Why don't you try one first before you jump in with both feet.

Cedar shingles or fence slats would work. Reread the part about how Daryl mounts them.

EHEHEHEH you know me, right?? :lol:

---------- Post added at 07:07 PM ---------- Previous post was at 07:00 PM ----------

I've been dreaming of spongy black lava with sphagnum moss cushions for them! The colors would really pop with black! Plus I think the lava is so porous it would dry out quickly. I live in a bog zone, never mind I've got plants all over the place. One Winter - don't ask me how - I had an uninvited 'house guest', a tiny frog who took up residence in one of my house plants :rofl: I took that as a compliment :biggrin:

I don't recall whether I put this in the lecture notes, but Daryl explicitly said not to use any moss when mounting Tolumnias. It leads to them rotting rapidly. They really do need to dry out fast. He said rocks get too hot. He uses cedar because it lasts the longest in his conditions.

"EHEHEHEH you know me, right?? "

I'm suspicious of your conditions. You could put them in clay pots and nest the posts into some kind of decorative container. But I honestly would start slow. Mine are under catt level light, clay pots, small bark. They dry out quickly. It's hard to imagine them in your set up. Just 'sayin.

Yes, I read that part about no moss. I think with my forced air heat and need to actually humidify, it might strike a balance. I think he's in Florida where am sure it's hot whether in or out of shade. I'm in the boggy PNW where the sun is weak at best in Winter, IF we even have any, so grow lights are a must in Winter. My sphagnum moss dries out very quickly when I put it as a top layer over bark for wetter loving orchids. Dunno, will have to experiment. Main thought was to cushion roots from sharp lava.
Another poster in another thread grew Tolumnia on lava rocks and they loved it! It has holes they can grip easily. His were outside it appears, so that's another story. I'll have a go of it and report back, I can always salvage it and move if it appears it's not happy. That's what I love about gardening and plants...I don't know how many times I've heard 'you can't grow that there' and I've done it. Used to astound the county ag man in Hawaii :D

---------- Post added at 09:24 PM ---------- Previous post was at 09:04 PM ----------

I do like clay pots over plastic, they seem to work well for my Phals and I can visually see the humidity line drop on the pots besides feeling the heft of them to know when to water. If anything, I have a problem of being too dry here inside.
Wouldn't the roots being outside of a clay pot and on lava rock give them an advantage of drying out more quickly? Maybe using coco fiber mats as cushions? I could do one up in moss and one in coco, see how those compare.

I have some overhead recessed lights that are directly above the fountain, could change those out to grow lights. Where there's a will there's a way. Paph's lower light requirement might do better, I'll check out minis. All I know is I gotta get some orchids growing around the base of that fountain! :lol: