Why My Guava Tree Leaves Are Yellowing?
Treating yellow leaves on a guava tree can be successfully achieved when the cause is revealed. These are the most common factors that lead to yellowing of guava trees.
Lack of sun exposure: Guava trees are tropical in nature and hence sunny conditions are essential for it to thrive. This fruit tree needs about 6 hours daily of sun exposure to maintain its green color an produce fruits. If your tree gets yellow because it was protected indoors during the winter, exposing it to adequate amount of sun after last day of frost risk has passed will return the lively green colors to your guava tree leaves.
Water balance: Keep the roots wet but don't overwater. If growing in a pot, it should be of decent size and have pores for draining. In hot and dry climates apply mulch around the trunk to preserve the moisture.
Nematode infestations: Some nematodes like to feed on guava tree roots. One way to help is to mulch the trees which will decrease the weed that attract the nematodes to the guava trunk area. If this doesn't work then treatment with a nematicide might help.
Lack of iron: This one of the common nutritional reasons for guava tree leaves turning yellow. Other nutrients deficiency also may play a role in this color change. Supplementing liquid chelated iron and am medium N-P-K fertilizer will boost both growth and fruiting of guava trees.
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