How long were they in the ground before they defoliated and died?

I ask because too little water is the most common reason woodies die within 2, sometimes 3, years after planting.

People water to the general vicinity when it's needed directly to the rootball in the early years. Sprinklers aren't enough.

I have two questions about my Weigela. First of all, I have a grouping of five and one is half dead (I think too much water near one side of it). Do I replace it or can anything be done with it. Also on one of the other Weigelas, I had a shoot of something else grow right out of the base of it. I knew it wasn't part of the Weigela, but couldn't identify it for certain and cut it to the ground last year. This year, it is back with a vengeance and I can now identify it as honeysuckle. I can cut it to the ground, but it will just come back. So how do I get rid of it without disturbing or injuring my Weigela?

It could be your root system was not that great to begin with. I have noticed over the years that I can buy a plant one place & get a weak root system & buy one at another place & get a great root system.
I always use a root stimulator when planting to increase the root systems of my plants & avoid transplant shock. I apply this once a month for the first 2 months. Also the first poster was right about watering the rootball area the first 2 years to get the plant off to a good start.
By me July & Aug are the months I have to really water a new plant in order for it to do good. Weigela's usually do very good without much trouble. That is what makes me think about how is your root system.

I also wonder about the condition of the roots. MW is very hard to come by in these parts and I have only seen them at one nursery. I bought everything they had (12) and inspite of the negative press I had heard, mine have thrived. I bought them mainly for the foliage texture and color and they have been more than I had hoped for. I never expected the incredible bloom I am now getting as we speak. All 12 are covered. I planted with G&B Soil Building Compost mixed with garden soil and Terosa and re-fertilized this spring with the Terosa and they are awesome.

Ok I have had a great deal of trouble with wine and roses but its new to me and maybe I too am not watering well enough at the rootball. The first one I tried was in good soil and I thought I watered it well enough but the next spring it never grew , never flowered , never leaved, just seemed to exist no matter what I did.

Gave up on that one. So I bought two more large plants and I watered them well all summer never flowered till just now I see light flowering. An expert told me they would not flower now this year. Wait till next year. So now I have hope. I also took cuttings of my wine and roses and it appears they are rooting and if they do I will plant them out in the spring.