Temperature drop to initiate flowering - Page 2 - Orchid Board

FinnBar · #11 11-15-2007, 04:56 AM

I appreciate the feedback, thank you all!

my days are around 24C/75F and i try to stay around 18C/64F at nights.
Ray, after i read the "set times for flower spikes" -thread i started thinking that going through all the trouble might be useful for my noid Phals. (i decided not to hijack the thread and started a new one.) i initially was thinking of my 6 Aerangis -articulata, biloba, citrata, distincta, modesta, mooreana- which grow inside a tank in the same room.

Now i also moved two phals in the tank, to protect them from the cold draft and to give them a steady 12 hours of light as our daylight hours are running really low by now.

markr · #12 11-15-2007, 06:38 PM

FinnBar, I grow several Aerangis species in conditions similar to yours (indoor terariums in northern Canada, heavily insulated and heated home, opening windows in the middle of winter is not practical). I don't have all the answers but perhaps my experiences will help you out a bit.

I have not experimented with the various growing parameters in a systematic way but my experience suggests that combining a slight drop in night-time temperature combined with a dryer period will initiate Aerangis flowers. I do not know, however, which of these two factors is primarily responsible for the spikes - I do both, simply due to "conventional wisdom" and lack of experimentation.
When I first put my orchids in terrariums I had a poor blooming year, possibly because I didn't pay attention to seasonal variations in temperature and water at all (although possibly for another reason entirely).

These days I open my windows in spring and autumn, before the outside temperatures get crazy low (-40C outside temperature in January is common here, which means the windows stay shut!). As little as three weeks of cooler nights (about 15C) and dryer days is enough to initiate spikes on all my Angraecoids and Phals.

Anyway, good luck!

FinnBar · #13 11-16-2007, 05:37 AM

Thanks Markr! i have a couple of additional questions, if you don't mind.

could you describe your watering habits for mounts during a dryer period?

do yours have certain bloom periods, especially related to their growth cycle? mine have grown new roots and
leaves are forming. does this sound like the time they could get into blooming..?

i've been fertilizing them lightly almost every watering until a few days ago when i switched to r/o only.

I got mine at the end of this summer so "we" don't share a long history together (yet)
I'm really into Angraecoids!

Thanks,
Antti

FinnBar · #14 12-05-2007, 11:49 AM

a recent update, after a few days of observation i can confirm a spike has initiated

on a phal!

Ross · #15 12-05-2007, 01:53 PM

Quote:

Originally Posted by FinnBar

Thanks Markr! i have a couple of additional questions, if you don't mind.

could you describe your watering habits for mounts during a dryer period?

do yours have certain bloom periods, especially related to their growth cycle? mine have grown new roots and
leaves are forming. does this sound like the time they could get into blooming..?

i've been fertilizing them lightly almost every watering until a few days ago when i switched to r/o only.

I got mine at the end of this summer so "we" don't share a long history together (yet)
I'm really into Angraecoids!

Thanks,
Antti

I'm not Mark, but I have had a long period with my angraecoids. Mine are in a large tank misted for 5 seconds every 5 hours during light-on cycle and dry at lights-off cycle. They are in basement and lights are the only source of light. During summer the basement is a bit warmer than right now. My days are approx 68F in the basement and in the tank under the lights about 73F. At night the basement is still nearly 68F and the tank temps drop to 68F. This is when the thru-wall fan kicks in and blows basement air through the tank for 3-4 hours. Just about every one of my mounts is either in flower spike or has just finished bloom and now putting out growth and roots. I have a complete description under the December Updates thread.

I really don't recommend switching to pure RO water for watering. Pure water is not good for the plants (ecept in misting) because it robs nutrients from the plant with continued use. I haven't changed my watering habits at all with the switch to cooler winter temps. I fertilize every-other-day or so and the misting goes on as normal.

FinnBar · #16 12-06-2007, 05:02 AM

Thanks for your input Ross.

Quote:

when i switched to r/o only

i'm not exactly sure what i meant by that...

probably that i started misting with r/o water only as i've never withheld fertilizer completely. well, anyway i've switched back to fertilizing daily either soaked or misted.

my humidity stays above 90/day with a drop to around 85
over the course of night. i water in the morning so the plants are dry by dark. with my "window ajar" routine days are around 74F with 65F nights.

moving them into the tank where they get a little more light than the windowsill apparently disturbed their leaf growth a bit but most of them have just finished a leaf.
apart from one the root growth is vigorous.

so are you saying they start their grow phase post-flowering?

Ross · #17 12-06-2007, 10:46 AM

Quote:

Originally Posted by FinnBar

Thanks for your input Ross.

so are you saying they start their grow phase post-flowering?

Not all of them. My Aerangis luteo-alba and A. citrata are both in active growth while also in spike. My A. fastuosa and A. hyaloids both slowed or finished leaf growth before spiking. Angraecum moniticola matured it's last leaf before forming a spike, Saccolabium kotense formed a spike which blasted then it started vegetative growth. There are many other examples both ways. So, no, I'm not suggesting they always go into growth stage post flowering, but some do.

FinnBar · #18 12-06-2007, 02:50 PM

i understand. i'll exercise my patience and look after them as well as i can. Thanks,
Antti