Is there a "season" for new roots?

[mascia]

Hi everyone,
I have 50+ mounted orchids and I try to check on them every week to make sure everything is okay.

Last week I noticed that all of the cattleyas started producing new roots at the same time, and at a really fast pace. My recently mounted walkeriana that was there doing nothing for over a month suddenly had 4 new root tips that grew to 10 cm (4" or so) in the blink of an eye.

So this weekend I check on them again, and now it's the phals, vandas, tolumnias and some oncidiums doing exactly the same thing, which got me curious.

Is there a time of the year when orchids focus on sending out new roots? Do you guys notice this in your collections? This is the last week of the summer, so days are getting shorter and temperatures cooler, so I'm thinking maybe it is related.

Thanks!