Multiply your options by planting many trees in restricted spaces
If you have room for just one stone fruit tree, you can squeeze in three. With space for two, you can shoehorn in six. How? Plant three trees in a triangular space not much bigger than you'd use for one.
This age-old technique triples your options. You can stretch the harvest of one fruit crop by planting early-, mid-, and late-season varieties--'Snow Queen', 'Heavenly White', and 'Arctic Queen' nectarines, for instance. Or plant two or three different fruit trees--a peach, a nectarine, and a self-fruiting plum.
Most stone fruit trees can be planted three-to-one. Just make sure the trees have comparable rootstocks--a tree with a standard rootstock will rapidly outgrow companions grafted onto dwarf or semidwarf stock. Find out whether the trees you want are self-fruiting or need second pollinators. And determine whether the area where you live can provide the necessary chill hours for the trees you want to grow.
Once you've decided on your triplets, here's how to plant:
1. Select a sunny, well-draining site where you can plant three trees in a triangle with the trunks spaced 18 to 24 inches apart.
2. For each tree, dig a hole that's broad and deep enough to accommodate the roots easily. (Cut off broken roots and shorten long, stringy ones first.)
3. Make a firm cone of soil in the bottom of the first hole. Spread the roots of one tree over the cone, positioning the plant so that the bud union is slightly aboveground and tilting the tree slightly outward. Repeat in the next two holes.
4. Backfill each hole with soil (mixed with organic amendments if desired), firming with your fingers as you fill. Water well. When the soil settles, check plant height. If necessary, pull the tree up slightly so the bud union is aboveground again.
5. On each tree, prune off any limbs that cross its center or reach out to cross the center of the neighboring tree. Cut each tree's main stem back to about 4 feet aboveground to force scaffold limbs to develop. Remove all but three or four well-spaced branches per tree, and shorten the remaining branches to two buds. In subsequent years, never allow any one tree to dominate and shade out the others.