It's interesting to read how vegetable and fruit (in the case of tomatoes) production can differ between countries and I hadn't thought about the requirements for growing in different climates until it was mentioned here.
I suppose we all take it for granted that we work our gardens/plots the same year after year and don't consider the difficulties of other areas. It would be interesting to visit each others countries for a year and see how we would cope growing in a different environment. I don't suppose for one moment that first year would be successful.
@Chuck my buckets are only 2 1/2 gallons so roots are more restricted than you thought. I grow in a multi purpose compost that I buy as I can't produce enough of my own and nutrients dwindle very quickly, however I don't start feeding until the first tomato has set. I have been discussing on another forum the effect of stress on plants concerning produce yields and it could be that the more a plant is stressed the higher the yield. I've noticed this with my house plants, if I forget to water them they will produce flowers. It's an interesting theory.
If you repeatedly stress plants, especially
Headfullofbees has mentioned light limiting growth and production, temperature obviously comes into that too. Around the solstice in June we have approximately 20 hours of daylight but that is no good without heat. The average summer temperature here on my island is quite low compared with other parts of Britain and this year we've only had a couple of weeks over 68F/20C which has been a day here and there, not continuous. Temperature today because it's raining again is 61F/16C.
Whatever country/area we live in we all have issues with our environment regarding growing crops of all kinds. We have few pests and diseases here to worry about in Britain but we lose out because of the climate. It's possibly the reverse for you Chuck?