Macoun
Apple in the US

Apples aren't usually started from seed if you're looking for a reliable fruit; most folks plant young trees or rootstock. If you fancy a challenge and want to try seeds, they need a cold spell first, called stratification, usually for a few months. Plant them about an inch deep in a pot or a sheltered spot after your last frost, or in late fall for natural stratification. Timing really depends on your USDA zone. For zones 5-7, think March, April, or even October, November. Warmer zones can start earlier, colder ones might wait until spring is properly here. It's a long game, mind, about 900 days from seed to harvest.

Once your young apple sapling is big enough to handle, you'll want to get it into its final spot. If you started indoors, gradually get it used to the outside world over a week or two – hardening off, we call it. Choose a sunny spot with good drainage; apples don't like soggy feet. Apple trees need a fair bit of room to grow, so give them plenty of space, maybe 10-15 feet apart for standard trees, less for dwarfs. You might need a stake for the first few years to keep them steady in the wind, especially in an exposed spot on the plot.