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Seedling problem.


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#1 Tha_Reaper

 
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Posted 21 March 2010 - 21:25 PM

I have a problem with my seedling darlingtonia all of a sudden.
I have sown them out-of-season in november after some time in the fridge, and as a result 29 of the 30 seeds germinated. Everything went perfectly well, untill this weekend.
Last week i have cut back the spaghnum because it was growing higher than the seedlings. By mistake ive cut 2 seedlings in half, but those are casualties of war. I've put them back in a ziplocj bag and put them back under 2 21 watt CF lights, where they have always been (the ziplock bag guarantees 100% humidity all day long for a long time).
when i just came back after a weekend away, i found that about half of my seedlings show shriveled tops of the pitchers and some even have shriveled tops of the stem, and i dont know what is causing it.
Truth to be told: this is the first time i am growing darlingtonia, so i also have no clue what a normal behaviour of the plant is.
can this be caused by the cutting of the spaghnum? that it suddenly recieves too much light or something? (with 42 watt CF light total that sounds so strange...)
can it be that they are just dying? (doom scenario)
can it be that the are going into hibernation because i started them out of season? (like i said: i have no clue what a normal darlingtonia seedling that goes into hibernation looks like, so it might be possible since i started them in november. Ive heard about people that grew darlingtonia under lights for 1,5 year straight skipping dormancy... how would it be possible that my plants are going into dormancy then?)

some photos (the camera never seemed to focus on the this that i wanted it to focus on... damn automated stuff...) hope it is of any help
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(click on the thumbnails to enlarge it)

any help/advice is appretiated

#2 MFS

 
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Posted 21 March 2010 - 23:30 PM

If you have them under artificial lights, the time of year should not matter at all. You are the one who regulates their photoperiod (i.e. decides how long they get light for).
Perhaps cutting back the moss has exposed the seedlings to drier air levels than they previously had, suddenly. If this is the case they can be shocked pretty hard. However you mention you keep them in bags, which I would think would rule this out. Another possibility is that the seedlings were shaded by the moss which was providing them with a natural canopy, and removing this has caused sunburn. I keep my cobras in the shade and they grow better than in full sun... However light levels from fluorescent lights should not even start to compare...
M

#3 Tha_Reaper

 
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Posted 21 March 2010 - 23:47 PM

they are on a daily 06.30 - 00.30 light schedule. I dont vary those times. A lot of the plants that i grow under those lights like D. intermedia and Dionaea go into dormancy themselves without a change in the light time, thats why i thought that my darlingtonia seedlings could do the same, and that the dying of some pitchers was a result of that.
The lower air humidity would be weird indeed because of the bags. The bags are always fogged up, and a hygrometer inside of the bag gave me 100% humidity at all times.
The shaded-by-moss-theory seems the most viable to me, but sunburn from CF lights... ive never heard of that before really. Its 42 watt total, provided by 2 lamps. Lamps are around 15-20 cm away from the seedlings. The whole wall of the space that i grow them in is covered in reflecting foil.

#4 Tha_Reaper

 
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Posted 04 April 2010 - 14:46 PM

it seems that the seedlings are fine.
the brown spots didnt progress, and the seedlings are making new pitchers closer to the spaghnum that ive cut back now, as if they are trying to form rosettes now

#5 jesse

 
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Posted 04 April 2010 - 15:15 PM

can it be that they are just dying? (doom scenario)


Temperature?

Darlingtonia need cool soil temperatures.

If you cannot find out the soil temperature: The daily average air temperature (with lights on and lights off) should be the same.

#6 Tha_Reaper

 
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Posted 04 April 2010 - 15:28 PM

15-18 degrees Celcius at night. around 25 at daytime.

#7 jesse

 
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Posted 04 April 2010 - 16:46 PM

15-18 degrees Celcius at night. around 25 at daytime.


Sounds pretty much. 16.5 at night and 25 at daytime is (with a photoperiod of 12 hours) a daily average (and most likely soil temperature) of 20.75°C.

This is not very chilly and in the absolute top range of summer temperatures recommended by many sources for Darlingtonia:
http://www.google.co...arlingtonia 70F
70°F is about 21°C.

I'd try to reduce the daily average temperature for them a little bit, if you cannot providy chilly soil by other means.