How To Plant A Tree
The larger the tree, the larger the hole you must dig. Dig a hole twice as wide as the root ball, and 10cm / 4" deeper than the root ball is tall. If you squash the roots into a small hole, you will inhibit growth. Fill the bottom with 5-7cm / 2-3in mixture of peat or compost and some of the soil just excavated.
Carefully remove the tree from its container, easing out any pot bound or very long roots and place it in the bottom of the hole, being careful not to break up the root ball. Make sure the tree's trunk is straight, and the tree's orientation if needed is facing the way. Fill the hole with more of the same planting mixture, firming in as you go.
Newly planted trees must be firmly staked for support. Place a stake into the ground alongside the root ball, but not through it, and hammer in securely. Tie the tree loosely to the stakes using tree ties, tie to the tree at the height of the stakes. Check the tree regularly, especially in the event of strong winds, which may lift the roots.
Water in very generously and apply mulch round base of tree. Keep a check on the firmness of the soil around the tree, particularly if there are strong winds.
When planting a tree in a lawn, do not allow the grass to grow right up to the trunk. Allow 60cm / 2ft around the base of the tree, keeping this clear of grass or other large plants for the first two years, to allow the tree to establish itself.