Answer: Unfortunately, based on your description I am not certain what is happening to your shrubs. I would suggest you work with your county extension to determine what is causing the dieback. If it is something that can be treated, they will have the most up to date information on what to use and how/when to use it.
Anthracnose on this plant would begin in especiallyu rainy weather and show as dark round or irregular leaf spots or little specks, then would spread until the leaf eventually yellows and drops off the plant. Careful cleanup and removal of infected foliage and fruit plus thorough leaf clean up each fall can help limit reinfection, also avoid handling the plants when they are wet. Based on your description, I don't think this is the problem.
In my experience alpine currants will tolerate a range of soils but seem to do best in soil that is evenly moist like a wrung out sponge, not saturated/sopping wet and not dried out. To know if you need to water, dig into the soil with your finger. If it is still damp, do not water yet. When you do water, water slowly and thoroughly and deeply so it can soak into the soil deep down where the deeper roots are. After you water, wait a few hours and then dig down to see how far the water went; sometimes it can be surprising.
I do not have a way to check which stores might have the Green Jeans in stock. Monrovia products are sold by independent retailers and they each have their own selection of plants, so you would need to check with the stores directly to see. There is a zip code based dealer locator at the Monrovia web site to help with contact information.
If they do not have them, you might try mail order. Bluestone Perennials for example lists it in their catalog.
I hope this helps.
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