>>1307868Someone else here, I'm regularly growing basil indoors on a southern window over the winter months when there's none in harvestable state outside (so basically late October to early/mid May), being at 50°N with really cloudy climate, they're doing fine mostly but struggle a lot during the darkest period of the year (mid-November to mid-January), during which I sometimes add alu foil behind or turn on grow lights in especially dark periods
Giving each single plant enough space (don't grow multiple ones just a few mm-cm apart but thin them if you start from seed) and rotating the planter every couple days helps