Lack of Fullness in Japanese Blueberry

Q. I was referred to you by Lori, a Master Gardener re: my problem with my Japanese Blueberry trees. I have planted 3  in November 2009, they are about 7 ft tall, 4 ft wide, trunk column about 3 inches in diameter . Leaves seemed to fall prematurely, browning and yellowish. One of the trees bark is peeling off and appeared to be dry. I have 3 sprinkler tubes on each tree, dripping 1 gl/hr each (I think). There's no visible insects but I do not know what to find anyway. Leaves seemed scarce, does not have that fullness that other trees does.  I have not sprayed them anything, no fertilizer or some sort. I put some manure compost 2 months ago. I am a novice on gardening so my description might seem funny. I can send some pictures if that would help. I have spent so much money on them for them to die. Please help.

Japanese blueberry along a block wall in rock mulch

A. Japanese blueberries will require a soil that is a composted at the time of planting and an organic mulch on the surface of the soil after planting.  It will do terribly in south or western exposures in full sun or in rock mulches.  If you planted this Japanese blueberry from a 15 gallon container then it will require about 15 gallons of water each time you water.  

The amount of water must increase from this amount as the plant gets larger from year to year.  This can be accomplished by adding minutes to your existing irrigation schedule at each watering or adding additional emitters.  If these are 1 gallon per hour emitters and there are three of them then the irrigation run time for this tree should be somewhere around 5 hours for it to get adequate water.  

Water requirement curve for the Las Vegas area. The first bar (1) is January
and the last bar is December (12). You can see that water demand by
plants increases 400% from January to July and August.

Unless this plant is getting water from other sources it will be under watered if you are irrigating for only one are 2 hours.  The frequency of application of the water, but not the number of gallons per application, will vary from season to season.  There is generally are a winter schedule, spring schedule, summer schedule, fall schedule and back too a winter schedule which means you should increase the number of times you irrigate per week about four times each year.  

These schedules will coincide approximately with December 1, February 1, May 1, mid June, mid September and finally December 1 which completes the seasonal cycle.  

Because your plant does not have the fullness that caught your eye I would assume it is due to improper irrigation which may have led to infestation with borers.  Pull off the loose bark at you see and look for damage in the wood do too boring insects.  This would include sawdust under the bark and perhaps elliptical exit holes from the trunk under the damaged area.  If the damage is more than half way around the trunk then I would replace the plant.