Pest & Disease Control for Guava Trees

Every fruit tree has the future potential for disease and insect damage. Factors such as location and weather will play a part in which issues your tree encounters. For all trees, proper maintenance (such as watering, fertilizing, pruning, spraying, weeding, and fall cleanup) can help keep most insects and diseases at bay.

NOTE: This is part 5 in a series of 8 articles. For a complete background on how to grow guava trees, we recommend starting from the beginning.

Stylar End Rot

Only affects fruit. The affected fruit’s bloom end turns discolored, spreading until the fruit becomes brown to black and soft. Infected fruits cannot be saved, but you can protect the remaining crop by using a fungicidal spray. To prevent reinfection, maintain cleanliness by picking up fallen debris, thinning Guava, and improving air circulation by creating distance between nearby plants after fruiting.

Fruit Fly

Flies lay eggs on ripe Guava fruits, and the hatched maggots feed on the soft pulp. Cutting open the fruits reveals the white maggots inside. Prune infected fruit and discard. You may also harvest the fruit before ripe. Use Safer® Brand Insect Killing Soap until harvest time.

Guava Moth

The moths lay eggs on growing fruits or nearby leaves. After hatching, the larvae enter the host fruit and cause damage that often goes unnoticed. Affected fruits either drop prematurely or become inedible when harvested. Prevent by removing leaves and other debris from planting area. Use Safer® Brand Insect Killing Soap until harvest time.

Anthracnose

A common fungal infection that causes dark-colored lesions on mature fruit. These lesions become covered in pink spores and can merge to form large necrotic patches on the fruit’s surface. Prevent and control with fungicide.

Aphids & Scale

These insects produce a sticky residue known as honeydew. This substance attracts ants, which form a symbiotic relationship with aphids and scale insects. The ants shield these pests from their predators and facilitate their spread, exacerbating the infestation. Prune diseased limbs. Control with Safer® Brand Insect Killing Soap until harvest time.