Sorry, but I have to do the conversion :-) 7 liters is just shy of 2 gallons.......and that is not enough water!! You want to water at the root zone slowly but thoroughly so that the entire rootball and surrounding area is fully hydrated. Not soaking.....just sufficiently moist. It may not be required daily......that is something you would need to check physically based on soil type and weather. With new plants, I just leave the hose in place at the base on a slow trickle until the water percolates down to the base of the rootball.

It could also be that the rootball itself was not properly hydrated before planting. In that case, it becomes almost hydrophobic and repels water.

Don't feed it. Dig down and see if the water is penetrating to the rootball. It’s a big transplant and given the weather at the moment I don’t think you’re overwatering, in fact 6 - 7l is not very much for a large newly planted tree. It’s only just over a watering can full. Can you give it 4 x as much every other day? Or run a hose on it for 15 minutes or so?

Wow really interesting @gardengal48 (PNW Z8/9) and @floral_uk z.8/9 SW UK, thanks so much.

I have been basing the amount on this advice for rootballs from the seller "Our guide for dry weather is to use at least 5 litres of water per metre of hedging twice a week."

Obviously I have gone above that, but sounds like not by enough.

I'll increase to on average 14 litres every day and see how it goes!

Many thanks again :)

Once again, everyday may be excessive. And don't rely on a predetermined amount. Water with a sufficient volume to hydrate the area as I described. Then allow the soil to dry slightly (but not completely) before you water again.

Are you wetting the foliage late in the day?

Will do @gardengal48 (PNW Z8/9), thank you!

Yes I am doing so @Embothrium

You don’t need to intentionally wet the foliage, just water at the base. But the weather’s supposed to break this weekend so your tree will get wet anyway. There’s no way to keep foliage dry in our climate.

The dead tips could be a twig blight resulting from the plant going into the night with wet foliage, at times when it wouldn't be doing so because of natural precipitation.

Since there’s no indication that this tree is on a slope it won’t have a high side or a low side so a berm is probably not needed. And to be honest I don’t think watering at night makes any difference in our climate. The RHS says either is fine. It’s the thoroughness of the watering which is important with a newly planted tree. We’ve had a lot of hot dry weather recently (by our standards) and that tree has a lot of transpiring foliage to support. Imo the key issue is insufficient water. It’s likely to get some rain this weekend but it still needs watering until established.

they are stressed .. from shipping from grower.. to seller to you ... fert is never a response to stress .. except from a grandma.. you you arent these trees grandma .. lol ...

next.. the already brown part.. are shipping damage ... they got injured being hioked around inmoving all over the place... snip out back to green growth ...

just in case.. interior yellowing and browning is normal.. and seasonal ... and can be increased by the stresses above.. i see little of that right now.. but warn you.. so you wont freak out ...

link below is a good primer.. look at section 12 ... and the section on mulching ...

https://sites.google.com/site/tnarboretum/Home/planting-a-tree-or-shrub

dig some small holes with a hand trowel.. or tablespoon .. AND FIND OUT ABOUT MOISTURE AT DEPTH ... no one can tell you about how water moves thru your soil.. in your yard.. in your location.. in your weather ...so you have to figure it out ...

but to be sure.. you need to get water down to where the roots are .. not just the surface .. and then let them near dry before you water deeply again ... once you get water down there.. and mulch.. you might not have to water for weeks or even a month.. depending on weather ...

except for the mechanical damage ... your tree doesnt look all that bad ... try not to love them to death ...

ken

A scattering of whole dead exterior twigs concentrated near the bottom of the frequently wetted plant will be a blight and not mechanical damage.

Thanks so much for everyone's responses, really appreciate it. Learnt an awful lot from all your comments.

And to answer @outpaientzero, yes we did water the hole beforehand and also used bonemeal and RootGrow.

During any future plantings skip the bone meal and root stimulator.

The Myth of Beneficial Bone Meal

https://s3.wp.wsu.edu/uploads/sites/403/2015/03/bonemeal.pdf

The Myth of Vitamin Stimulants

https://s3.wp.wsu.edu/uploads/sites/403/2015/03/vitamin-b1.pdf