Deflasked seedling die off

[Rowangreen]

Thanks for the thanks, but I didn't actually say anything *G*. I'll post what I've done if you like, but it is less than 3 weeks.

[Stray59]

yes rowangreen, please do post! Mine have mostly died off within 3 days of planting, so I am sure there was a pathogen in the soil mix. I have just deflasked some Hawkinsara seedlings, STERILIZED EVERYTHING, and potted them in compots with coco chunks on bottom, and some shedded NZ spaghnum on top. So far so good. In this time (about 12 hours) I had noticed die off in some of my others. The Hawkinsara are all still green, no brown spots. I did use a mild Captan solution to fight fungus, which is an old standby that I had forgotten about. I have used it on all types of seedlings in the past, but haven't thougnt about it in several years. Keep you kingers (and anything else) crossed!
Steve

[Rowangreen]

Does sound like clean medium is a big factor then! I used chopped moss as I've heard it has some anti-fungal and anti-bacterial properties. I damped mine down (with de-ionised water as pabstias are reputed to be very sensitive to water quality), microwaved it for a minute or two then let it cool before planting. Just about everything else used was washed with 10% bleach solution, but rinsed with ordinary tap water. Seedlings were just rinsed with tap water, no treatments (My tap water is hard but otherwise good quality I believe).

Set up: a propagator. Leca in the bottom, with water. Some plastic trays on top of that with the plant pots (and an atmosphere monitor) in them. I have a heat mat below but have only used it for brief periods. I've tried to keep it between 20 and 25C. It's been at 99% humidity most of the time (according to my monitor: I suspect it can't say 100%!) First week I kept it closed. After that I started leaving the vent open which didn't seem to reduce the humidity! So I've been leaving it with the top off for short periods to expose the plants to bursts of lower humidity. They are going down to 70-80% several times a day now, so I'm going to start leaving it with the top off for longer now.

No problems at first (much to my surprise!) and I'm seeing quite a bit of growth, both roots and leaves! I have now got a couple of roots looking not brilliant and with spots of mold. However for now I'm holding off doing anything (keeping fingers crossed...). It's been there a few days and the plants are looking fine/have other growth, so I'm thinking it may even be just a bit of growth medium that was left (I decided against actually scrubbing the roots clean! So hairy paphs and delicate Pabstias did get a bit left!)

They have had (I think) 3 little sprays of water with a little fert.

I don't actually have a fan at the moment! Thinking of looking at getting one... but to be honest I've got a lot on and maybe won't get round to it. I'm hoping temperature differences will be enough to create a few air currents! After all, people do succeed just with plastic bottles!

So... some possible fungal problems developing, possibly due to lack of air movement. But so far that doesn't look serious. I've also got to tackle tranfer of media at some point: I might keep the Pabstias in moss as I'll be watering them with de-ionised anyway. But moss doesn't generally work for me as I need to be able to water heavily and flush due to my hard tap water.

Another thought: some of mine were de-flasked on the early side (Pabstias due to contamination, phals because they were growing so fast I was afraid they'd be breaking out before the propogator was available for another batch!). I'm not sure this was a bad thing really, as they all came out in active growth, which has continued so far. Maybe leaving it as long as possible can sometimes lead to plants that are a bit stressed by the time they come out?

Anyway, good luck with yours! And I'll be keeping my fingers crossed mine keep going well! (and microwaving any new media!)

[Stray59]

Rowangreen;
I have been away (yes, I had to leave the newly planted Hawkinsara seedlings on their own for a few days), but upon my return I am proud to say that I have not lose even one.
I pulled about 110 plants out of the bottle, planted them in STRERILIZED NZ peat moss that I ran through a food processor in order to get a fine texture. I soaked the seedlings in B-1 start-up, a transplanting and stress reducing hormone. I also soaked them for a while in Captan and then directly planted into the sphagnum which is resting on damp coco chunks. So far so good, but I will keep you updated. As per the humidity, I again resorted to my seedling case, where I am able to keep 70% humidity with lots of air movement. Not a sign of fungus and the plants seem to adjusted just fine. Again, will keep you posted.
Steve

[greengarden]

I lost a lot planting into bark, this time I used a 50:50 mix of fine coco peat and perlite and all of them are looking great quite a few weeks after deflasking(the medium was not sterilised but both of these aren't prone to fungal issues). These ones were also Dendrobium spectabile which I have heard can be finicky so i am very pleased with the results, especially as many now have roots filling the pots! They are in tiny terracotta pots which are sitting on a bed of sphag inside a plastic tub, no fan at all. I start by putting cling wrap over the top to completely seal it, after a few days I left it open at a corner and have gradually made the hole bigger over a few weeks and I now leave it completely off in the daytime and cover them at night. I have watered only with demineralised water at this stage.

[Stray59]

Rowangreen;
Sounds like you have mastered raising seedlings! Really happy for you. The more orchids for the world to enjoy! What do you do with all your offspring? I am starting an internet store, hopefully, - right now just seeing how Ebay pays off! I have a lot of stuff to move along, and several orchids that I need to thin down. I was giving my spare to a local museum greenhouse, but they have a viral, fungal and bacterial epidemic, yet will not discard any of the infected plants, will not require sterile pruning of plants, etc. I sort of hate to give a plant away that I know is doomed.
Any way, thanks for all you input, keep me updated on your developments; will try to do the same!
Steve

[Rowangreen]

This is my first batch of seedlings, and only totals 14 plants between them, so I'm not at capacity yet! Spares might go to my orchid society (they let members sell them with 10% to the society at most meetings, but prices tend to be cheap). Long way off yet though! I think I'm a long way from declaring success.

[Stray59]

Keep after it! It sounds like you have a good approach to raising the seedlings though. Just looked at mine and they are still all thriving. The orchid society is a good idea for sales. I still need to join the society here; I just moved into the area a little while ago and still need to 'set root'. Will let you know how it all goes.
Steve