A very nice and compact plant. Mine had ugly long internodes ...

I think now it's the time to start new growths, right?
It will be a good indicator of its adaptation to the new environment.
From what I've been reading it might not resist my winter outside due to:

- Max temps are low (12 ºC - 53 F avg)
- Rainy season coincides with low temps

Two solutions:

Built a small greehouse to protect from the rain (and keep monitoring to see if it adapts to these temps).

Put it inside during the rainy season.

Do you have a balcony or something with a roof, where it could stay outside without getting wet.

Not really but I can protect it with some kind of plastic or build a greenhouse.

I compared Canary Islands climate with mine and you have much higher temps in winter.

The temperature is not too low. People grow them outside on trees in southern California with a similar temperature range to yours, and cold winter rain any time between October and April.

In habitat it is true they receive no rain in winter. If mounted you could move it under a cover during a winter rainy spell, then move it back when the weather dries.

About a year ago Roberta mentioned they only produce roots once a year, so it is best to wait to move them until new roots are just forming.

The best to initiate its acclimatization to lower temps is to put it outside as soon as possible, after root growth.
It might start soon 'cause now we are having day temps around 59~68 F (15~20 ºC).
See here.

This is true for the coastal towns; in the mountains the tº are much colder.

estación seca mentioned they only produce roots once a year - that's right! So every lost root is a little debacle. Be very careful with them!

I've often wondered why things that are possible in California don't work here - there must be a part of weather we do overlook.

Could it be humidity? Most of Canary Islands have a semi-arid / desert climate.

That is strange. Canarian plants do extremely well in coastal California, all the way north.

Of course, and I would like to grow a blue Ceanothus here if only I could get one!

But you can not compare bushes (echium) or hapaxantic growth forms with epiphytes like orchids.
Our bushes are summer - heat - dormant and re-green with the first rain. These bushes don't mind if the summer stays wet, as long as there is dry air, sun and good ventilation. They thrive well in continuous wet and fresh conditions, like in our mountains in winter, when there is every day clouds, and fog, and rain (horizontal rain, mostly = condensed fog on the branches and leaves).
Orchids from semiarid regions need a dry and cold rest and rising humidity makes roots appear - than begins the rainy season - and the warmth.
I'm now trying to grow Dendrobium speciosum outside. But if you compare the rainfall pattern from Brisbane with ours - both more or less 28º latitude -, you'll notice that the rainy month are the warm months, there too.