Water the young plants thoroughly in their trays, and leave them to drain for an hour or so.
Dig over the chosen area thoroughly and remove any weeds. Spread a bucket (10l) of well matured compost and a handful (60g) of 2:3:2 fertilizer per square metre. Dig this into the soil to a depth of about 15cm, rake to level the area and water thoroughly.
Remove the seedlings from their tray cavities by support the stem with a finger on either side and gently push the plant from the bottom, keeping the soil intact around the root ball.
Ensure that the plant is placed in the soil at the same depth as it was in the container. Gently firm the soil around the roots to remove air pockets in the soil without compacting the soil too much.
Water well with a fine rose so that the soil is not washed off the roots. Feed regularly with a water-soluble plant food for best results.