Could have been a poor root-ball on that particular arb. It doesn't look good and it probably will continue its decline. If you have a warranty I'd wait until next March/April and use it then if it does continue its decline (or whenever ideal dormant planting time is for your area.)

Dax

Dig around and look to see if the root-ball is dry or wet. Since you bought and planted the stock in May probably the root-ball was getting dried out when you bought it and has never been completely re-moistened since. Much field stock is planted in fine textured soils that hold together nicely for balling in burlap but later repel water if allowed to dry out between the field and the final planting site.

I see field grown 'Smaragd' sitting around drying out at big box stores here every year. Many of these also have tiny balls in relation to the size of the tops - there may be a percentage of regular failures due to not enough roots having been retained at digging for the plant to be able to take up enough water to make it through the following summer (without special treatment).

if you have a warranty ... return it in sept ..

while you are dragging it out of the ground.. take some pix of the roots.. and/or let us know ... what you find ...

meanwhile ... dig a small hole [hand trowel, 3 to 6 inches deep] next to the root mass you planted.. AND FIND OUT IF THE SOIL IS WET OR DRY... crikey. its pretty easy to find out if its wet or dry ...

may as well do it on a few of the others... to compare.. and check those ...

ken

i might suspect that the planting berm ended a bit short.. and is not shaded.. and that that side of the root mass dried more.. or stayed hotter.. than the rest...

in addition to the possibility.. that the mass was bad to begin with

ken

thanks to all. we will check out the root ball and let you know our findings. thanks so much for the replies and for the help.