From Ground: Firstly, water the hairy vetch plant to dampen the soil around the rootball. Then, use a garden spade to dig around the plant with a wide enough margin to leave the root ball intact. Carefully work the spade under the root ball to lift the plant from its location. Try to keep as much of the root structure as possible when removing the plant.
From Pot: First, water your hairy vetch plant well. Then, carefully turn the pot upside down or lay it on the side, and gently ease out plant and rootball. Do not pull by the stem or top growth as you might damage the plant. Sometimes, lightly tapping the bottom of the container can help.
From Seedling Tray: First, ensure the seedlings have developed enough by checking if they have at least 2 to 3 true leaves. Gently push up from the bottom or use a pencil on the side to lift the rootball and seedling out of the cell. Always handle by the leaves, not by the stem.