Open a trench approximately 200 mm deep, with a flat bottom, approximately 200 mm across.
Lay the crowns down one side of the trench, 200 - 300 mm apart. Make sure the buds are facing up.
Plant another row of crowns along the other side of the trench, but in the gaps of the first row.
This gives a staggered double row with 7-10 plants per m length of row.
Cover the crowns with 5 cm of loose soil. DO NOT fill the trench with soil. This will ensure the crowns get away to a good start.
Slowly fill the trench with soil during the following summer and autumn, as you hoe any weeds on the sides of the trench.
By the following winter the trench should be filled with soil, and the soil surface flat.