How much success have you had rooting old rootless Cattleya back-bulbs.

[Orchid Whisperer]

I wouldn't dismiss any root growth stimulant, as long as you know what's in it (I don't use Super thrive - nope, not me). Kelp extract, go for it. I've used KLN successfully (must have been a fresh batch, if not fresh, it won't work).

If the plant tissue is my capable of making roots, stimulants can work. Not all plant tissues can make roots, quite old back rhizomes are probably less capable. IMO, best hope on a back bulb is for the plant tissue to be hydrated enough for a dormant lateral meristem to start growing.

[K-Sci]

Originally Posted by Shadeflower

Backbulbs that have lost all their roots can become rehydrated again but the more vigorous the hybrid the more noticebale it will be, ...
I would like to introduce exhibit "A":
<snip>

We're not quite talking about the same thing. What I'm referring to as back-bulbs are far older than your plant. Two examples are the crinkled old 'Muse' back-bulbs in my last post.

I've attached a photo to illustrate. The plant on the right, Lc. Bryan Wheeler 'Grandson', was moved up to a larger pot last year without removing media. The oldest backbulbs from are somewhat shriveled, probably due to repotting root loss perhaps 8-10 years ago. The rest of the plant is thriving, but the old bulbs never fully plumped up again.

On the left is Lc. Betty Ford 'York', which had to be divided to fit it in the pot last year. All but the most forward bulbs are very deeply shriveled due to the root loss and will probably never be fully plump again.

Most of the back-bulbs I'm trying to root are like those of the plant on the right -- perhaps 8-12 years old.

K-Sci

[K-Sci]

Originally Posted by Orchid Whisperer

...
If the plant tissue is [] capable of making roots, stimulants can work. Not all plant tissues can make roots, quite old back rhizomes are probably less capable. IMO, best hope on a back bulb is for the plant tissue to be hydrated enough for a dormant lateral meristem to start growing.

I'm inclined to agree. The big challenge is getting the water into the old de-hydrated back-bulbs.

I have a mounted C. violacea that is 13 bulbs in a single un-branched vine. Only the oldest bulb has lost its roots. If it were grown in a pot, several of the oldest bulbs would have died by now. Bulb life is limited for most potted sympodials due to the root loss that occurs when trimming the plant to fit in a new pot. It would be nice if we could train them to grow in a nice neat spiral.

k-Sci

---------- Post added at 10:13 AM ---------- Previous post was at 09:43 AM ----------

Originally Posted by Orchid Whisperer

...I've used KLN successfully (must have been a fresh batch, if not fresh, it won't work)...

Mine is dated not to be sold or used after April 28, 2022. Can this be considered fresh?

K-Sci

[Orchid Whisperer]

Originally Posted by K-Sci

k-Sci

---------- Post added at 10:13 AM ---------- Previous post was at 09:43 AM ----------


Mine is dated not to be sold or used after April 28, 2022. Can this be considered fresh?

K-Sci

I'd at least give it a try. TBH, that KLN I used was years ago, I don't recall it having a date. I had read (again, years ago) that KLN tends to lose potency. It's good that yours is "use by" dated.

[Ben_in_North_FLA]

sometime we over complicate the plant's desire to live. I have occasionally tried getting barely alive back bulbs to sprout a lead and roots. 2 easiest method I have found are putting the bulbs in a clean small empty clay pot and just keep it in same environment that mother plant is and second mounted on a piece of tree fern totem and , again, place back in same environment that mother plants. Both times the bulbs sprouted and become normal size in a couple of years. Cool to see the progress from growth to larger growth to eventually blooming lead. No special materials needed, just some patience.
If I had to do more I would just do the tree fern method as cattleya love to get their roots embedded into tree fern.

[realoldbeachbum]

Wow K-SCI, how do you keep those clay pots so clean? Mine have white (salt? Calcium?) dust on them. It comes right back when I clean them. Good job!

[estación seca]

In cactus and succulent societies, people showing plants learn to wipe clay pots with a little olive oil just before the show to make them look nice and clean.

[SouthPark]

Originally Posted by K-Sci

Questions: Is it worth the effort? What should I expect for success? What kind of success have you had rooting old partially shriveled rootless back-bulbs like these? What methods?

One answer for 'is it worth the effort?' is ----- maybe for myself it is worth the effort ----- but don't know about other growers. It's always statistically a mixed bag.

For those particular rootless back-bulbs that you showed in your opening pic ----- I'd say in my tropical conditions over here, ones like that would probably be approximately 100% success rate.

This is assuming that they still have what they call 'eyes' that are still alive. Little tabs or stubs that can grow into a shoot (new bulb).

I have read that if an orchid does get into a really bad shape, then the eyes can become destroyed, so that absolutely no new shoots could possibly be produced by the existing structure.

But - on the other hand, I think I also recall at least somebody indicating the possibility of new growth - regardless of 'eyes' all being destroyed ------ as long as the plant can develop roots and stay alive for long enough.

But - in any case - if the goal is to maximise chances of getting shriveled back-bulbs to first sprout roots, followed by sprouting new shoots, then the usual procedure applies in general ------ provide good conditions like suitable humidity, and lighting, and suitable temperature.

A little bit of root growth hormone/stimulant (eg. ezy-root gel that I have here) can help.

Adequate humidity is good ----- because if the humidity isn't adequate, then eyes could start growing while existing bulbs keep shriveling - and the new growth can abruptly take a plunge in health and not make it. But at the same time - if the orchid is placed in ICU (into a humidity tank) ----- then we might also need to keep an eye on unwanted activity ----- eg. fungal activity. So some gentle air-movement may help. Fungicide could also be considered if needed later.

It's different from say an orchid seedling flask environment, where no nasties get inside.

Also --- for the case of rootless back-bulbs, but also for the condition where those backbulbs are still connected to the 'colony' - along with all the other bulbs ...... some growers mentioned that they 'partially' sever a portion of the rhizome ---- which sort of leaves two portions partially connected, and they reported that it might trigger some eye growing response. It's an attempt at producing leads in locations where they probably wouldn't have otherwise developed.

[Shadeflower]

I hadn't even noticed the immaculate pots. I was admiring the mass of growth above

Ps: K-sci I can understand your reluctance to use boosters. Plants without roots are in a vey fragile state so I try not to use boosters, I'd say I get good results from being careful not to use too many chemicals when the plant hasn't got many roots but it's hard to say, I've lost and saved rootless plants trying kelpmax and not.

The most important and far more important than any additives is getting the plant not to dry out too much and not too wet that is start rotting.

There is no big secret what method to use except what seems to work for you (keeping the plant from drying out or rotting) and I think moist sphagnum moss with a bag placed around it (leaving an air gap at the bottom) is a popular method. I use an aquarium myself if I need to maintain a high humidity.
I'd recommend you give the plant a good rinse if you keep it in a high humidity environment and remove any dead leaves. The substrate will stay wetter than you are used to if it is more humid so you do need to pay attention it doesn't get too wet because it will not dry as easily.

It's a learning experience for all of us. I am constantly learning from my orchids. Getting the humidity right is still always a challenge as just tiny changes can make big differences, like lava stone is not all the same, some lava stones might have formed around a solid pebble. You notice this if certain stones grow more algae on them - so you can never just pot up an orchid and leave it - you constantly have to judge how much you need to be watering and if the substrate needs adjusting by the next repot.

[K-Sci]

Originally Posted by realoldbeachbum

Wow K-SCI, how do you keep those clay pots so clean? Mine have white (salt? Calcium?) dust on them. It comes right back when I clean them. Good job!

Reverse osmosis and rainwater with only an occasional hosing off. Very little in the way of salts to accumulate.

-Keith