Planting out bare root trees

The reason why they are usually planted during the dormant period is because the plants can be shipped without fear of drying out. Once they start to leaf-out, they could dry out before they arrive at your house. To heavily water them would add a lot of weight to the parcels (and make the delivery van rather wet if it leaked!).
If a growing (leafed-out) tree is out of the ground for more than about half an hour, it can be severely dehydrated and can take months to recover.
If planting bare-root trees at this time of year, get the hole dug and everything to hand before unwrapping the roots, to prevent the roots being damaged by dehydration.

Also, trees send out a burst of root growth just before they start to open flowers or leaves. That burst of root growth helps establish them.
It seems as if most root growth happens in early spring or in autumn. That also coincides with a time when the leaves are not active and the soil is moist (so roots can easily push through the soil). Besides; roots will not grow into dry soil (some people think that roots search for water; in fact, they grow into damp soil); yet another reason why root growth often slows in the summer.

By all means plant some now, but be aware that they will be more dependent or regular watering than a dormant-planted tree that will by now have grown-out some new roots into the surrounding soil. I suggest not pruning them until next winter at the earliest.

If you take good care of them, I expect that in a couple of years, they will be indistinguishable form any that were planted at the correct time of year.

If you buy some, please take note of the rootstock (or any size guide).
Also consider that many of the shop-bought varieties need heavy spraying to remain healthy and productive. But there are many disease-resistant varieties out there that can survive extreme abuse and neglect. The kind of disease resistance you might need will depend upon your local climate.

I am very grateful for the detailed and helpful reply FB. I want to take advantage of the different fruit trees currently on offer. I will follow all of your advice.

Many thanks

Rob

For some info on my experiences with certain varieties, have a read of this:

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