Irish people are OBSESSED with the weather. No work day starts without a summary of current conditions, (as if people weren't fit to see it for themselves but anyway) followed by a prediction of weather to come which is based on the Irish 'spidey sense' and an early morning analysis of the colour of the clouds. The conversation is most always followed by a grimace and a sigh. In case any of you are unfamiliar with the general climate here on the Emerald Isle it can pretty much be summed up in two sentences. It rains a lot. It is sunny very rarely. But on the bright side we usually have quite mild winters and without the rain we'd be a lot less 'emerald'. Anyway I've just realised that my introduction has gone on a bit of a tangent and my real point is about cooking in season!
Knowing what fruit and veg are grown in your country and in what times of year is very important to the environment and to the quality of the food you eat. Eating in season cuts down on the giant carbon footprints that are created by ships and airplanes transporting food from one country to another. It also means that less chemicals are used on the food you eat as they do not need to be preserved for as long or withstand transit. Cooking in season also naturally mirrors your body's food cravings. In summer our bodies want light, cool food full of water, e.g. strawberries.
I mentioned the weather in my introduction as of course it has to be excepted that some foods just cannot be grown in your home country. Global warming is going to have to get seriously worse before you can grow a pineapple on Irish soil. So realistically you can't be expected to cut everything out of your diet that isn't available in your country but you should be aware of country of origin on the food packaging and try to cut down on long haul foods.
I found a great website for foods in season in Ireland http://www.bestinseason.ie/whats-in-season/, a bit of googling should result in the same sort of information for your country.