One of Sweden’s most wonderful aspects of nature is the midnight sun up in the north, close to and beyond the polar circle.
Some people are fine with going to bed when it is still light, others become true night time people and don’t go to bed until 6 or 7 am. A lot of people who move to the north have a lot of trouble sleeping, desperately pulling down blinds to darken rooms enough to catch a couple of winks. Either way people who have lived in the north of Sweden for a long time are probably used to the long hours of daylight during the summer and the extreme lack of the in the winter whether they enjoy theses extremes or not.
However, in southern parts of the world there are no landmass which corresponds to the northern latitudes where you can experience the “midnight sun”, so a phenomenon such as the midnight sun is exotic and exciting and something some hope to get to experience once in a lifetime.
Many French and probably other nations get their summer holidays in August and travel up through Sweden to finally reach their destination only to find that it has already started getting dark. From the 21st or 22nd of June (the midsummer solstice) it gets a little darker everyday. So the light, even though it is associated with summer has very little with the fact that it is warm etc.
If you want to see people out gardening at 2 am in the morning then you should try to go in the month of May or June. Definitively a sight to be seen.