Plants under stress often react by setting an abnormal number of fruit buds. This helps insure the survival of the species even if the parent plant dies. So lots of fruit buds were set during 2018. Those buds matured into flower and then fruit (seeds) during 2019. Think back to last year. I have never seen certain plants bloom as well as they did last year. Maturing this much fruit takes a great deal of energy. I think this resulted in such low energy levels in the fall that the plants just didn’t have enough energy to make it through the winter or may have delayed leaf out. Areas with too much rain last summer had that additional stress added to the mix. Roots need oxygen as well as water and too much rain can damage root systems.
So what do we do? The only thing we can do now is try to avoid any further stress. Basically that means watering during dry weather. Don’t overdo it as too much moisture can damage root systems. The goal is to keep the soil moist but not waterlogged while allowing the top of the soil surface to dry between waterings. (Ward Upham)