Welcome to the My Citrus Tree Symptom Checker

Symptom Checker

We’ve developed this Citrus Tree Symptom Checker as a tool to help understand what citrus tree symptoms could mean. Above all, GrowScripts feel that the best way to identify what is wrong with your citrus tree is through a visual examination. Therefore, within this section, we are bringing together and sharing the resources that help identify things wrong with a lemon tree, lime tree, orange tree, grapefruit tree, or tangerine tree.

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Citrus Canker

#1. Citrus Canker

Young Citrus Canker lesions on leaves with prominent yellow haloes and water-soaked margins. In addition, there are many times looks like a yellow halo with an oily ring around it.

​Symptoms

Defoliation, Fruit drop, Blemishes on fruit, Blister like lesions on fruit, Round holes in leaves, Raised corky lesions on fruit

Treatment

Copper

citrus greening

#2. Citrus Greening

Early symptoms of yellowing may appear on a single shoot or branch. After that, the yellowing usually spreads throughout the tree over a year, especially on young trees.

Symptoms

Yellowing along the veins of normal sized leaves, Blotchy-mottle on leaves, Chlorotic (yellow leaves), Out of season flushing/flowering, Dieback in severe cases, Small lopsided fruit, Unpleasant fruit flavor, Fruit not coloring properly

Treatment

Micronutrients; NPK Fertilizer

altenaria brown spot

#3. Citrus Alternaria Brown Spot

Spores of Alternaria are airborne. In addition, most spores are produced by lesions on mature leaves on the tree or recently fallen infected leaves in the leaf litter from the tree.

Symptoms

Corky outgrowth on leaves, Citrus Scab (Click Image to view, shoots, and fruit), Wart like growths

Treatment

Copper

Greasy Spot

#4. Citrus Greasy Spot

Greasy spot is a disease caused by fungus. Symptoms appear as yellow to dark brown to black lesions occurring first on the underside of mature citrus leaves.

Symptoms

Spores on underside of leaves, Yellow spots on upper side of leaves, Irregular brown blisters that have a greasy appearance, Leaf drop

Treatment

Copper, Foliar Micronutrient

Phytophthora

#5. Citrus Phytophthora

When roots or tree trunks are affected, the foliage turns yellow and exhibits poor growth, leaves drop, twigs die back, and fruit size and yield are reduced.

Symptoms

Bark peeling at ground level, Redish-brown resin from trunk

Treatment

Thyme-Guard, Preventative Fungicide

Sooty Mold

#6. Citrus Sooty Mold

Sooty mold is a black thin mat that is the result of massive, superficial fungal growth most commonly occurring on leaves, fruit, twigs, and small branches.

Symptoms

Black thin mat on fruit and/or leaves

Treatment

Horticultural Oil

Aphids

#7. Citrus Aphids

Citrus Aphids are closely associated with new growth flushes and newly, emergent, succulent leaves. In addition, the color of Aphids can be light green-yellow, grey-green, brown, or black.

Symptoms

Little bugs on plant

Treatment

Thyme-Guard, Imidacloprid

Leafminer

#8. Citrus Leafminer

Symptoms of infestation include curling of leaves and serpentine mines on the lower and upper sides of leaves. Similarly, the epidermis appears as a silvery film over leaf mines.

Symptoms

Curling leaves, Serpentine mines on the leaves, Silvery film over the mines

Treatment

Thyme-Guard, Imidacloprid

Citrus Psyllid

#9. Citrus Psyllid

The Asian citrus psyllid causes damage by feeding because they attack young tender growth (flush), causing leaf distortion and curling. In addition, the psyllid also produces honeydew, which leads to sooty mold infestations, and badly-damaged leaves will die and fall off.

Symptoms

Leaf distortion and curling

Treatment

Thyme-Guard, Imidacloprid

Spider Mite

#10. Citrus Spider Mite

The mites feeding causes graying or yellowing of the leaves. Necrotic spots occur in the advanced stages of leaf damage. Similarly, Mite damage to the open flower causes a browning and withering of the petals that resembles spray burn.

Symptoms

Scratchy leaf in a stippled-bleached effect, Leaves could turn yellow, gray or bronze at later stages

Treatment

Horticultural Oil, Imidacloprid

Rust Mite

#11. Citrus Rust Mite

When rust mite injury occurs on young fruit before fruit maturity, epidermal cells are destroyed resulting in smaller fruit. After that, epidermal cells become brownish-black and rusty looking.

Symptoms

Small Fruit, Brownish/Rust looking fruit

Treatment

Horticultural Oil

The Source for Answering Questions That Start With My Citrus Tree Since 2010

Since the beginning of the MyCitrusTree campaign partnership in 2010 with Record Buck Farms, this citrus tree symptom checker (under KeyPlex Direct until 2014; and GrowScripts thereafter) has helped many homeowners find what is wrong with their citrus tree.

From the questions we’ve gotten over the years, there are a few main ones that always come up. In addition to the diagnostics tool above for visual aid in identifying citrus tree issues, we can say that the biggest questions are: