|Tree gave fruit 2 years ago and nothing since. Tree is healthy and robust. I need to know what fertilizer to use and when to use it.|
The tree needs lot of light to fruit well. Use a lawn type fertilizer such as 15-5-10 or similar blend in spring and summer. You may also want to add some potassium magnesium sulfate (K-Mag or SulPoMag) when you apply the other fertilizer. I suggest you also contact your county extension office to inquire about making the Lychee more fruitful. They have experts available in such types of fruit.
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