Any thoughts on why half this Red Flowering Currant died off

Half this Rubus sanguineum (Red Flowering Currant). The shrub is in full sun until sometime in the afternoon. North facing, but open to the eastern sun. It could be about 8 yrs. old ?

Thanks Fran

 

At first glance, this looks like a root problem. Other plants in the photo, including the lawn, indicate that there is plenty of water so it's possible too much water has caused a root or crown rot. Ribes sanguineum is notably drought tolerant and needs good drainage. Overwatering and/or poor drainage can lead to root rot.

Did you notice how the leaves looked before they fell off? There are a few fungal diseases that can afflict currants but it's hard to tell now unless other leaves on the shrub are beginning to show symptoms. It would be strange too for leaf fungi to affect only some of the leaves on a single plant.

I found quite a bit of information on the Home Guides site that might be useful . . . Flowering Currant Diseases They include White Pine Blister Rust, Powdery Mildew, Botrytis Blight as well as a bit of info on root rots.

 

Until what time in the afternoon? Is the damage on the S side of the plant? Ribes sanguineum is not particularly heat resistant, so the damage could be caused by the excessive heat.
I don't know about Ladner, but here where I live in the Kootenays we have a bad heat wave now.

 

Here where I live on Vancouver Island, Ribes sanguineum thrive in full sun with no water other than what nature provides. It would be interesting to know how your plant fares over the next year; please keep us posted.

 

I heard several reports about sudden die-off with Ribes sanguineum at a recent garden club meeting. There might be something else going-on below soil--fungal?

 

One of my two r. sangeuineum planted in south Seattle died earlier in the summer. First the oldest branches abruptly died, the leaves dried out turning brown. Six or eight weeks later the rest of the plant but the dust in the same manner. It appears totally dead now. Salal is growing well nearby.

 

Suggestions elsewhere online suggest root rot, including this answer from Extension.org: ribes sanguineum - Ask an Expert