Meanwhile, the Penjing plants must be grown in greenhouses with mesh screening of less than 1.6 mm 2 years before export, and 0.6 mm 6 months before export.

同时，出口前2年须种植在网径小于1.6毫米的网室中，出口前6个月须种植在网径小于0.6毫米的网室内。

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The finer mesh and cone shape moves liquids through faster while screening out even tiny lumps, Mr. Bridge says.

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