Common Problems While Growing Guava Tree

The guava tree fruit grows on a small tree with a wide, short canopy and a sturdy single- to multi-stemmed trunk. The guava tree is an interesting plant with mottled greenish bark and long 3- to 7-inch about 7.5 to 18 cm serrated leaves. 
Guava trees produce white guavas, 1-inch about 2.5 cm flowers that yield small round, oval, or pear-shaped guava fruits. These are more accurately berries with soft flesh, which may be white, yellow, pink, or even red, and which vary in taste from acidic, sour to sweet, and rich depending on the variety. Guava plants thrive in any soil with well-draining conditions and full sun for best flowering and fruit production. 

Keep lawns back from the root region of your small guava trees. While grass is one of the few things that can somehow manage to grow underneath your guava plant, any damage from lawnmowers or weed whackers to the trunk can put it at risk of disease.
Similarly, if your lawn is even near the root system, be cautious about guava plant fertilizer. Lawn fertilizer often has high nitrogen levels which can cause your tree to produce lots of foliage and little guava fruit. As the roots often extend out past the guava fruit tree canopy, limit your lawn fertilizing within proximity of the tree.

• Overwatering can cause many issues with guava trees, root rot being among those. Make sure your soil is well-draining.
• For home growers, keep your guava trees at 10’ or shorter when possible. The weight of the guava fruit combined with any serious wind can make it unstable, and you don’t want it to fall over.
• Leaf tip burn or browning has been documented in areas of saline soil mix, such as those near coastlines. While this typically is not severe enough to cause lasting damage, it’s something to be mindful of.

Guava Fruit flies, Mexican fruit flies and Caribbean fruit flies are a common pest. To prevent these, harvest before the guava fruit is fully ripe. Pick up any fallen guava fruit, and make use of fruit fly traps as needed to reduce their numbers.

Red algae, also called algal spot or algal leaf spot, is caused by the fungus Cephaleuros virescens. This condition creates purplish-brown spotting on guava plant leaves and can, if severe, cause defoliation and lowered fruit production. Treat with a copper-based fungicide to prevent diseases.
Another common fungal problem in guava trees is anthracnose. This disease can also be controlled and treated with copper fungicidal sprays. Another most common is leaf spots which appear also are treated with copper.
Finally, fungal root rots can develop in overly-wet conditions of Guava. Ensure the soil is in a well-draining condition readily to prevent this from occurring.