No greenhouse fruit is sweeter or more luscious than a peach or nectarine plucked sun warmed and fully ripe. Indeed this should be a balloon full of nectar just waiting to burst on you. Now if you live in a warm sunny area you may just be able to win a crop of peaches outdoors in good years, but without glass seldom will you ever manage nectarines. And although these two fruits seem different they’re closely connected, almost twins, as nectarines are sometimes borne on peach trees and vice versa.
The nectarine is more plum like, not fuzzy, even more luscious and requires just a tad more warmth. Otherwise both peaches and nectarines require identical treatment and were traditionally grown in a greenhouse border for reliable crops. However planting them into the ground is now seen as a serious mistake as they stay so much healthier when grown in large tubs. In the ground they do get much bigger necessitating more pruning but the problem is in winter the ventilation needs to be left fully open to give them a winter chill to ensure they go dormant and this may not suit other occupants. But the worst problem of permanent housing is the slow build up of pests and diseases. By growing them in tubs and moving them outdoors from mid summer till mid winter they stay much cleaner, and after experiencing a couple of chill months are dormant enough to be brought under cover to flower and crop. I bring mine in during mid January as left out much longer they may catch a fungal attack of leaf curl. Once indoors the sheltered conditions soon bring them into flower, their pink blooms can be prettier than many purely ornamental shrubs.
Hand pollination with a small paintbrush is recommended as few insects are available. Then if the set is good it pays to thin the small fruits ruthlessly- I leave them a hand width apart, this ensures fewer but far larger fruits, leaving too many means many will never ripen. Good ventilation is important as they do not want great heat but otherwise their management is simple with regular watering with a dash of liquid feed. Any reasonably free draining potting compost, preferably well enriched and with a bit of lime in it suits them and they are not at all difficult to manage. If you can only have one I recommend a Peento type peach such as Bonanza which has oddly flattened fruits but crops reliably and the bush remains very compact. Peregrine and Rochester are another two reliable peaches and there are many many more. Nectarines used to be available in many varieties but now few are offered save the old favourite Lord Napier. Unlike with other fruits it may be worth you raising your own peach or nectarine from a stone- these are very quick (by fruit tree standards) to crop and may do so in only five or six years from sowing.