Making sourdough bread in various places

Back in Avignon, I've got my starter for sourdough bread. It's been alive now for a few years and as I make bread weekly, it is refreshed regularly. I've got my stash of multi-grain flour, the honey from my beekeeper, the sea salt, etc., It's a very regular and dependable act for me to make bread in Avignon. My bread comes out nicely airy, with a good crust, sweet, tender... mmm my mouth waters as I think of it. I store my starter in a glass jar in my fridge, which is pretty new and not too cold, but cold enough. (My renters found it not cold enough for their milk, so they turned it into an igloo, but that's another story). I change jars for the starter relatively often, so they are clean, etc.,

I started a starter at JP's last year, during one of the school vacations when I was there longer than a weekend. However, I don't use it too often, and thus don't refresh it very regularly, and in any case, his fridge is way less cold than mine. This, plus the fact that his oven is rather dinky-- can we say simple and minimal needs' bachelor?-- and that I'm often up to other things there and might forget the rising bread (most particularly as I've tucked it out of sight so it isn't on the counter in his way), leads to some less than successful bread making attempts at his house. In general, the bread is heavier and more acidic at his house, lighter and sweeter at mine. So, it's edible, but not truly mouth-watering and yummy.

Here in Michigan, I've got a starter going, and I made one good batch of bread, but the second, well, I wasn't there to plop it in the oven at the ideal moment, and the air is cooler so the rising was difficult to time, and there is more humidity... My second batch turned out heavy, dark and more acidic. It's not bad, but it is akin to the dark, grain-filled Norwegian bread that is often sold in health-food stores in France.

So, what to learn? Sourdough and starters, the rhythm necessary to bake good bread, the attention to time, temperature, humidity, ovens, all are variables that shift the final product. A basic fact is that I live most often in my Avignon home and thus have figured it out. Whereas these other homes find me flitting in and out. Or, is it in the air? the atmosphere? Can one take this as a symbolic of something more?