Hi huda. I've never heard of olive vines. Olives grow on trees. On the way to murree from Islamabad they have tried experimenting with olive cultivation, but I'm not sure if it was fruitful. The natural habitat of olives is the Mediterranean region. I've seen olive groves that are thousands of years old there. I don't think tropical Karachi will suit it. The senior members may be able to guide you better.
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