I have Miracle fruit plants which have flowered in 18 months. Fertilise with high P:K: soluble Fert, like "GreenCare" every two weeks.
I added some NPK and micronutrients in the hole while planting.
Interesting thing is that my uncle never gave any fertilizer to his plant.
But there are 2 differences:
1. My uncle planted in full sun and I planted in partial shade.
2. Uncle water his plant twice in a day and I water once in a week
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