Botanical Overview
Guava is a member of Myrtaceae, the Myrtle family (Myrtaceae), and Psidium, the
guava genus, which contains nearly 100 species, most of which bear edible fruit. Psidium
guajava: Guava, is the most commercially important. Hundreds of cultivars have been developed
world-wide in tropical regions.
Description
Form:
A single to multi-stemmed shrub or small tree.
Lifespan:
30-40 years, but productivity declines after 15 years.
Leaf retention:
Evergreen.
Growth rate:
Moderate to rapid.
Mature Size:
6-12' (1.8-3.7m) high and as wide. In topical climates, it can reach 30' (9m) high.
Flowers:
Five white petals, hundreds of white stamens tipped with pale yellow anthers.
The petals drop quickly, leaving hairy tufts of stamens.
Bloom:
Spring and early fall. In the right location and weather conditions, it may bloom nearly
all year. A second crop usually does not mature in regions where temperatures drop below
50°F (10°C) in winter.
Self-fruitful:
Yes, but some cultivars produce more fruit when cross-pollinated with another cultivar.
Years before fruiting:
2-4 grafted, 5-8 from seed.
Fruit:
Light-green or lemon-yellow when ripe, round, oval or pear-shaped, 2-4" (5-10cm) long.
Guavas are often placed in two categories: white (or yellow) flesh and pink (or red) flesh.
White fleshed guavas are sometimes eaten before they are fully ripe when crispy.
Pink fleshed cultivars are eaten when ripe.
Seeds are numerous and small; hard and inedible in white fleshed fruit, softer and edible
in pink fleshed fruit. The flavor varies tremendously among cultivars.
Months for fruit to ripen:
3-5. The fruit are ripe when strongly fragrant and the rind softens to be fully edible. Fruit
on the plant ripen at various times, not all at once.
Storage after harvest:
The fruit will continue to ripen after being picked and last 3-5 days at room temperature if
ripe. After just ripening, if refrigerated without wrapping, they will last up to 4 weeks.
Leaves:
Medium green, ovate to lance-shaped, stiff and thick, aromatic when crushed. They may develop
purple blotches on top in cold weather, a normal condition.
Stems:
No thorns. The bark is a mottled reddish brown color and peels off in flakes.
Roots:
Commercially grown guava is usually grafted onto a specially chosen rootstock. In regions
where hard freezes occur every few years, however, non-grafted trees can come back from their
roots after a freeze and are preferable for residential owners. Pink fleshed guava are
reportedly more cold hardy than white fleshed varieties and will come back from their roots
quicker after a hard freeze. Guava roots are shallow, often producing suckers. Guavas are
invasive in wet tropical regions such as Hawaii and Florida.
Cultivars of Note:
'Allahabadi' – Deep pink flesh, excellent
flavor and aroma, developed in India. The skin turns from green to red when ripe.
'Hawaiian Pink Supreme' – Excellent flavor.
'Mexican Cream' – Excellent flavor, smaller
fruit size.
Wildlife:
The flowers attract bees. The fruit attract birds and mammals.
Toxic / Danger: No. However, a chemical compound in the
leaves acts as a cardiac depressant and is contraindicated for some heart conditions.
Origin:
Southern Mexico and Central America.
Cultivation and Uses
USDA hardiness zones: 9b-11. Young plants are
frost-tender and must be protected from freezes. Mature trees can withstand brief periods of
27°F (-2.8°C). Trees three years and older can sustain some dieback in regions with
freezes, but will recover.
Guava plants stop growing when temperatures drop below 50°F (10°C).
Chill hours:
None.
Heat tolerant:
This plant has difficulty over 110°F (43°C) and is severely stressed over 115°F
(46°C). It needs daily irrigation to survive high temperatures.
Some varieties will also require afternoon shade over 100°F (38°C) to keep their
fruit. A few leaves may turn yellow but will green up in cooler temperatures.
Drought tolerant:
No. In high temperatures, guava will need irrigation every one or two days.
Sun:
Full sun except first year plants and certain varieties that need afternoon shade when
temperatures exceed 100°F (38°C).
More than afternoon shade causes the plant to become spindly.
Planting:
Locate in full sun, possibly next to a south-facing wall with afternoon shade, away from low
spots where cold air collects in winter.
These plants cannot be grown in containers due to their rapid growth and need for an
extensive, shallow root system.
They can be grown as bonsai, which involves pruning their roots every year.
Soil:
This plant tolerates a soil moisture range of well draining to some water saturation. High
organic content in the soil improves performance; it tolerates pH 5-8.2 (strongly acidic
to alkaline).
Fertilize:
Apply organic fertilizer in February, May and August, spreading it under the canopy and 1'
(0.3m) from the trunk. A plant micronutrient solution, applied once a year in February, in
irrigation water, will supply zinc which increases fruit production.
Water after becoming established:
Because of their shallow roots, Guava need shallow watering as often as every one or three
days during the hottest part of the summer, to every one or two weeks in winter.
Fruit drop signifies insufficient water.
A bubbler irrigation system on a timer may be best.
Mulch:
Use organic mulch under the canopy and 1' (0.3m) from the trunk to conserve moisture and
reduce weeds.
First Two Years Care:
Water every one or two days in the first year. Provide 50% afternoon shade. Do not fertilize
until new growth starts. Remove weeds within 3' (1m) of the plant to avoid competition for
nutrients. Pull weeds by hand rather than using tools to avoid damaging the guava's shallow
roots. Protect from freezing.
Prune:
After the first two years in the ground, guava produce more fruit when heavily pruned every
winter.
To thin fruit in warm months, use needle nose clippers.
Never pull fruit off a branch.
When fruit is the size of a golf ball, remove any fruit that [1] grows straight up from its
branch, [2] any fruit touching another, and [3] any fruit too close to the trunk.
It's a good idea to have fruit growing on alternating sides of the branch, as this will more
evenly distribute the weight.
Flowers and fruit appear mostly on new growth.
Litter:
Fruit if not harvested.
Propagation:
Cuttings or buds grafted onto seedling rootstock. Softwood cuttings, treated with rooting
hormone, and planted in starter mix in a mist enclosure. Air layering with rooting hormone.
Seed is variable and does not grow true to the parent.
Uses:
Edible fruit served raw in salads, cooked to make juice or jelly, canned for later eating,
used in pie and cake recipes, ice cream flavoring, and more.
Comments
Other names are Common Guava and Yellow Guava.
Strawberry Guava: Psidium cattleianum, is a closely related species.
It is more cold hardy but far less heat tolerant.
Pineapple Guava: Feijoa sellowiana belongs
to a different genus. It is more cold hardy, deep rooted, and easier to grow. It has smaller,
delicious, exotically flavored fruit.
Do you have additional information or a different experience for these plants that you would
like to share? Email info@GardenOracle.com. All contributions are welcome and appreciated.