Almost all peaches are self-fertile and require no pollinators. They will set heavy crops on single trees, which need heavy and aggressive thinning early in the season for best fruit size. Maintain good vigor in peaches by pruning every year, and fertilizing moderately. Aim for 1-3 feet of new growth a year. Fertilize early in the season, so that growth is well hardened off before fall and winter cold weather.
Gala peach was bred more for southern conditions where it does very well. Grandpa doesn't recommend it for the northern climes where winter conditions are less mild and more extreme.