Feijoa (Feijoa sellowiana) is native to South America, but can be grown in subtropical climates like Hawaii, southern California and Florida. It's more of a shrub than a tree, with a bushy spread and height of up to 20 feet at maturity. Sometimes called the pineapple guava for the shape and taste of its seedy, mild fruit, feijoa can be planted for ornamental purposes as well. It can be left to follow its natural growth habit, or you can prune it to the shape of a small tree.
Prune feijoa for shape in late fall or early winter, when the tree is dormant and less vulnerable to insects and diseases that can infect pruning wounds. Sterilize pruning tool blades before use by dipping them in boiling water for 30 seconds or wiping them with a cloth dipped in rubbing alcohol.
Prune away all branches, shoots and suckers from the lowest third of the feijoa's trunk. These branches and shoots will not produce fruit, and removing them will give the feijoa a more treelike form. Set the blades of pruning shears at 45 degrees and cut down and away from the trunk, leaving a short stub that will drain moisture and heal fast.
Examine the feijoa's canopy for vertically growing branches. Thin them out with long-handled pruning shears to let in more light and air to the remaining branches. Leave healthy branches that grow at a 60- to 90-degree angle from the trunk intact.
In the spring and early summer, look for crossing and rubbing branches in the canopy, especially as fruit begins to develop. Rubbing causes bark injury and fruit spoilage. Again, prune away the weaker branches, leaving the strongest alone.
Prune out dead, diseased or storm-damaged branches as you see them, at any time of year. Leaving damaged branches on the tree will reduce its vigor and it will yield less fruit.
Cut up prunings and discard them in yard waste bags. Sterilize pruning equipment before storage or use on other trees to avoid communicating insect eggs or diseases.