Spike production temps
 

I've read (Linsey A. Newton1 and Erik S. Runkle2,3 Department of Horticulture, Michigan State University, A288 Plant and
Soil Sciences Building, East Lansing, MI 48824) that high temps for several hours inhibited phals to produce spikes. Have any of you read this paper? Your thoughts on it?


http://www.hrt.msu.edu/faculty/Runkl...ering_2009.pdf.

I haven't read that particular one, but I did read an article once (while shamelessly exploiting work's access to online journals!) that temps of 28 degrees C or over will inhibit spikes and growth of a spike (if these temps were introduced before the spike was 4 inches in height/ length). I may have to explore the journals again in my limited 'off-time' as I really can't remember where I found this!

Someone here once said (might have been Camille) that the large mass producing phal nursaries keep Phals in a warm greenhouse for 18months to trigger high growth but no spikes. Then because they have been inhibited from spiking for more than 12 months (the usual spiking period) when the green house is switched to lower temps they all spike at the same time ready for sale.

No idea what temps are involved. And that is talking about more constant high temps than just for several hours. But it does confirm high temps can inhibit the flowering.

Howdy
If I remember right, and some of this was also published in Orchids magazine by Runkle and Dr. Wang, spikes are encouraged when temps are between 75 and 65f--autumn season (they don't need the shock of 55). And, they remain in a grow cycle for as long as the day temps remain above 75 consistently. once the spike is so long, it continues to grow and develop, unless the temps get out of hand, then it may stall, or abort.

My own situation seems to bear it out, and why keikei grow works so well in the summer when the temps are warm, and the plants are wanting to grow.

my two cents

Take care
Rex
AKA POLKA