I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
Your question is a difficult one as sprays that would kill the vines and weeds would most likely damage the junipers. If hand weeding simply cannot be done you may want to try carefully wiping a product with glyphosate or triclopyr directly onto the weed foliage but just don't get it on the junipers. Otherwise I can't think of an option for those weeds growing amongst junipers.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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