Pineapple Guava (Feijoa)

Feijoa is hardy through zones 8 to 11. In zone 8, where winter lows can reach the plant's limit, site it against a south wall or other sheltered spot, mulch the root zone, and cover or wrap young plants when a hard freeze is forecast. Late-hanging fruit is the first thing to lose. The wood itself is injured below about 20 F, but fruit is damaged at 28 F, so a freeze that leaves the plant untouched can still take a crop that is still hanging. Established plants shrug off brief dips that would kill an unprotected young one.

Unless you are growing 'Unique', set a second, different feijoa cultivar close enough that pollinators move freely between the two. 'Precocious' flowers profusely over a long season and makes a dependable pollen parent for whatever else is blooming. If you have room for only one plant, you can instead graft a second cultivar onto the same rootstock. Feijoa pollen is small and poorly carried by wind, so the crop depends on bees and birds moving pollen between plants. Self-incompatible trees preferentially outcross, and honeybees are weak pollinators here because they tend to work flowers within a single tree rather than travel between them. Apart from 'Unique', every named variety is at best partially self-fertile and sets a larger crop when pollinated by another variety.

Starting in late winter and continuing through fall, apply a complete fertilizer such as 10-10-10 or 8-3-9 every 4 to 6 weeks. Keep each dose small: 0.5 to 1 lb per plant for young plants, and no more than 2 lb per plant for mature ones. Feijoa also wants magnesium and sulfur plus the micronutrients boron, nickel, manganese, copper, zinc, and iron, which you can supply granularly, through fertigation, or as a foliar feed. Feijoa grows slowly and takes up nutrients steadily rather than in a flush, so many light doses spread across the season suit it far better than one heavy spring application.

Prune only enough to build and hold the form you want, whether that is a hedge, a multi-stemmed shrub, or a single-trunk small tree. Shorten individual shoots to check spread or to open up a crowded canopy, and take out dead or crossing wood. Repeat lightly in summer if the plant is outgrowing its space. Resist the urge to shear it into a formal outline. Feijoa needs very little pruning beyond structural training. It does tolerate heavy pruning and shearing, but every cut takes off the wood that would have carried flowers, so a tightly sheared plant trades its crop for a neat outline.

An established feijoa needs no routine irrigation in a normal year, but once fruit is on the plant, water it through any prolonged dry period. Water deeply and infrequently rather than lightly and often. Feijoa is drought tolerant but responds to a long dry spell by shedding both fruit and leaves, so a drought during fruit development costs you the crop outright rather than merely shrinking it. Consistent soil moisture is what carries fruit through to good size and quality.

Look over the stems and leaf undersides for black scale, and watch ripening fruit for fruit fly stings and soft breakdown around the puncture. In the southeastern US expect to find nothing most years. Where the rainy season overlaps bloom and fruit development, an occasional fungicide for anthracnose fruit rot may be warranted, but treat only in response to a problem you have actually found. Feijoa has no consistent pest or pathogen threats reported in the southeastern United States. Black scale and fruit flies turn up in California, and scale, thrips, fruit flies, and anthracnose rot are reported in New Zealand and South America, but none of these are dependable enough anywhere in the US to justify a calendar spray.

Wait until the first fruits drop on their own; that is your signal the crop has begun to mature. From then on, spread a tarp under the plant and shake the branches lightly, or pick only fruit that detaches with almost no force. Some softening and a color change to a lighter green also indicate ripeness. Feijoa ripens unevenly over a long stretch, so plan on repeated passes rather than one harvest. To eat, halve the fruit and scoop the pulp. Feijoa lets go of its fruit when it is ready, and detachment with minimal force is the cue commercial growers harvest by. Fruit pulled before it will release is astringent and gritty, so the plant's own abscission is the most trustworthy indicator — softening and a lighter green are supporting signs.

Move mature fruit into cold storage at 32 to 40 F as soon as you gather it, where it will hold for 4 to 7 weeks. Fruit left at room temperature is good for only about a week. Sort out any bruised or split fruit before storing and use it first. A whole feijoa crop matures across a couple of months but each fruit has a short shelf life once it drops, so cold storage is what turns a glut into a supply. At room temperature the pulp browns and breaks down within days.