if u germinated them first probably a couple days do this, make sure ur soil is moist then put a ziploc baggy over it keep it in the dark for a couple of days or it might pop up over night, mine did with this method good luck, and remember marijuana doesnt grow over night... paticence my friend. Ur fellow grower Dank
provided they were already germed, it should only take a day or two to sprout provided you didn't plant them too deeply.