Answer: Without knowing precisely what's causing the damage, it's difficult to recommend a control strategy. You'll need to put on your detective cap and thoroughly inspect your banana plant at various times of the day; early morning, mid-day and early evening, when caterpillars and other chewing pests are most active. Caterpillars leave behind frass (little black pellets) so check closely for those tell-tale signs. Other chewing insects often leave no physical signs (aside from plant damage) and they can come and go before you even notice the damage they have done. Once you've found the culprit, if you can capture it and take it in a sealed plastic bag to your local nursery center, they can identify it for you and recommend control strategies. If you cannot find the pest, it's possible that it has moved on and your plants won't suffer any more damage. Keep in mind that wind can cause banana leaf tear and shredding, which may appear to be insect damage but is in fact weather related.
Best wishes with your red banana plant!
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