This is a question I get asked all the time, so here’s a guide for you.
Start by watering the plant in the pot, give it a good soak when you get home so it can handle the stress of planting better. Place the plant in the proposed location while it is still in the pot, this is a good time to make the final decision on if it looks good where you thought you wanted it. Check every angle, stand back, sit in your favourite chair or look out windows. Its your last chance to change your mind.
Scrap away any existing mulch. Dig the hole twice as wide as the plant is, it will only need to be a little deeper than the original pot. Take the plant out of the pot and place it in the hole, make sure the plant stand’s straight. If the ground is rocky or really clay based you can choose to remove the dirt and backfill with a quality garden soil. If the soil is friable reuse what came out of the hole. Water the plant with a generous amount of water, this is the most important watering you can give a plant, this will settle all the small soil particles around the root ball.
Check every angle, stand back, sit in your favourite chair or look out windows
Stake the plant so it can move but cannot be blown over, the movement you allow here will encourage the plant to secure itself into the ground with solid roots and to thicken the girth of the trunk so it can be self supporting later on.
By overstaking trees you trick them to think they have a thick trunk and they put all the time into leaf growth which eventually snaps the trunk with leaf weight.
Slow release fertilizer, dynamic lifter or other organic fertilizers are beneficial or a liquid feed or seasol is also recommended. Reapply the mulch to a level of 10cm thick, scrapped back from the trunk to ensure no fungal problems.
You do not have to stamp the plant into the ground, this just snaps the root system under the ground.
You do not have to tie the plant rigid to a stake, we mentioned this earlier.
You do not have to dig the hole twice as deep as the pot size
You do not have to dig the hole twice as deep as the pot size, twice as wide is much more beneficial.
Try not to only use a orger, this will glaze the side of the hole as it spins, this does not allow the roots easy penetration into the surrounding soil. Use an orger then break the walls of the hole with a crowbar.
You do not have to use expensive osmocoats or other fertilizer in the hole, osmocoats are designed to be used in potting media not gardens, fertilizers are better left under the mulch not in direct contact with fresh root systems.
You do not have to water the plants every day, try a small amounts every few days while they establish. Plants need oxygen near there roots to promote growth. Being drowned in water will slow down growth to compensate but understand you don’t want your plant to dry out either