PESTS
Mealybugs, scale, aphids, & spider mites are all common pests for Alocasias.
Prevention
▹ Inspect your plant often & treat as soon as you see them.
▹ Keep leaves clean & dust-free by wiping them down regularly
▹ If plant has an infestation, spray with insecticidal soap or neem oil to kill adult pests & their eggs.
{SEE BELOW FOR SPECIFIC TREATMENTS FOR PARTICULAR PESTS}
CROWN, STEM, & ROOT ROT
Crown, stem, & root rot is due to a fungus in the soil, often caused by wet conditions & heavy soil. This will have negative effects on the plant, causing damage to the crown, stem, &/or roots.
Common Signs
・While the rot will eventually engulf the entire plant, most times the first sign of problems will happen at the soil line or on one side of the plant.
・Your plant may become stunted, failing to produce any new leaves.
If the plant is rotting, there may be a foul odor, mushy stems, & droopy leaves.
・How do you check?
▹ Gently pull on the seemingly affected stem; if it is sturdy & will not wiggle in the soil, it is probably not rotten. However, if the stem feels week & wiggles easily, it's most likely there is rot somewhere in the stem.
Treatment
Unfortunately, rot usually goes undetected until it is fairly advanced.
{ 1 } Remove the plant from the infected soil & repot in fresh, new soil.
{ 2 } Apply a fungicide. Drench soil with treatment for a minimum of two times per 30 days.
{ 3 }Trim back the affected foliage, leaving only the leaves that are healthy.
{ 4 } Repeat this process until only healthy foliage remains.
POWDERY MILDEW
A light gray or white powdery substance found on the plant's leaves.
Unfortunately, powdery mildew is commonly found on Alocasias.
This fungus thrives in warm, dry climates, however, it will also form in areas that do not receive enough aeration.
Common Signs
This problem is pretty obvious. Not only is it easy to see, it is also relatively easy to diagnose as there aren't many other conditions that resemble it . You'll know your plant is being affected by mildew if you see powdery white patches on your plant's leaves & stems.
Treatment
・Make sure your plants are adequately spaced. If your plants are too close together airflow can become constricted, which will lead to powdery mildew.
・Make sure your plant is receiving enough light. If your Alocasia is in low light for a prelonged amount of time, especially after watering, the soil may have a hard time drying. This will eventually lead to growing fungus.
・Remove dead or diseased foliage with sharp shears or pruners.
▹ Make sure you disinfect your tool after each use - this fungus could spread to the next plant your tools touch!
・Purchase & use an organic fungicide with sulfer as the main ingredient. Use this treatment by coating all infected areas at least once per week for ~1 month.
LEAF SPOT
Leaf spot is caused by a fungus that grows on the leaves of your plants, causing them to turn brown & splotchy. As the disease progresses, the circle will grow in size, eventually causing your plant to lose leaves & show signs of overall ill health.
Common Signs
Small brown spots will begin to appear on the leaves of your plant, eventually spreading out.
▹ These splotches will cause the leaves to die & fall off.
Your plant may look wilted & stunted
Treatment
・ISOLATE the infected plant immediately! This fungus can spread & will infect your other plants if you aren't careful.
・Make an organic treatment or buy an over-the-counter treatment.
▹ This concoction must contain sulfer & copper octanoate.
・Mix 1/2 teaspoon of baking soda per 1 gallon of water. Use the solution to wipe your leaves & spray the stems.
XANTHOMONAS INFECTION
An infection caused by bacteria that leads to necrosis, causing small brown spots between the leaf veins, as well as crumpled & wilted leaves on your plant.
Common Signs
・Small brown spots along the veins of your plant's leaves, which ultimately cause them to curl up & die.
・Lesions on the fruit, stems, & roots are evident.
・In some cases, the spots are so large & raised that they cannot be missed.
Treatment
⚠︎ There is no treatment for this disease!
・Quarantine your plant.
・Cut off all dead or dying leaves.
・ Try to stop the spread by using hydrogen peroxide as a disinfection treatment.
・Try to stop the spread by incorporating biological antagonists in the soil to help good bacteria fight off bad bacteria.
MOST COMMON ALOCASIA PESTS
SPIDER MITES
Small yellow or brown insects that can destroy a houseplant in a matter of days.
Common Signs
・If you look very closely you may be able to see the mites, however they are incredibly small.
・Look for powdery white webs that cover all the leaves of the affected plant.
・Sometimes mites will cause leaves to become discolored as they break out with thousands of tiny dots.
Treatment
Spray the plant with high pressured water from the hose. These insects do not like water & will often be defeated quite easily with this simple method. However, sometimes this isn't enough, especially for a large infestation.
Insecticidal oils & soap prevent & kill existing spider mites.
MEALYBUGS
Soft-bodied, wingless, white & cottony insects found on the leaves & stems of plants. They feed on the sap of the plant's leaves & stems.
Common Signs
・White clumps at leaf nodes, on the underside of leaves, along the stem, & especially in the nook where leaf meets stem.
・You will find more mealy bugs on new growth (new leaves, new stems, etc.) than you will on any other part of the plant.
・These bugs leave a waxy film on the plant.
Treatment
・Easy to wash off with high pressure water from the hose. This is a great first line of treatment.
・Use your fingers & pluck them off/kill them manually.
・Wipe the leaves with a solution of (at most) 70% isopropyl alcohol & 30% water.
・Use insecticidal soap or neem oil.
SCALE
There are many types of scale. Each type comes in a different color, shape, & size, however, the most common type is a small, brown, & rounded lump found on your plant's leaves & stems. It comes in a soft & hard scaled variety.
Common Signs
・Small round lumps inside the leaf.
・Small, brown, & rounded lumps on the plant's leaves & stems.
・Secretions, which lead to sooty mold.
・Yellow, wilted, &/or weathered leaves & plant.
Treatment
・Dip a toothbrush in rubbing alcohol.
・Rinse your plant in the sink or shower to wash away any bugs you've missed.
・Following a trim of all of the dead & damaged foliage, use an organic or chemical pesticide.
・Use diluted neem oil weekly until plant returns to good health.