silver streak dianella

This variegated variety of the Dianella tasmanica was spotted in a garden in Tagaytay City. I've seen this plant in gardens before but what caught my attention was its lovely and unique purple berries. Now I'm curious about its pollinator and why the plant here in Manila is not producing berries.

Thank you to Emma for identifying this spotting and this link http://www.worldplants.com/Dindex.htm