What is the cause of yellow blight or moss on the branches of a weigela tree?
The shrub has etiher yellow moss fungus or a yellow lichen. These articles should help: https://www.gardeningknowhow.com/ornamental/foliage/moss/moss-on-plants.htm
My weigela bush did not produce any buds this spring, but now (middle Sept) it is covered in flowers. When should I prune or would it be best not to do anything to it this late in the season?
Odd that it is blooming now, but hold off on pruning until blooms fade. Normally you prune these shrubs back folling their blooming in spring. Here is more information: https://www.gardeningknowhow.com/ornamental/shrubs/weigela/pruning-weigela.htm
Can Weigelas be trimmed back in late September. Thanks.
This article will help with pruning: https://www.gardeningknowhow.com/ornamental/shrubs/weigela/pruning-weigela.htm
I've purchased a new home with many neglected flowering shrubs. I'm zealous to get them in better shape. It is fall now. My weigela shrubs seem to have a disease on the old leaves. I don't know if they will all come off during winter. I want to orune them away now, but I know I'm not supposed to prune till after spring bloom. I also want to a avoid chemicals. What do you suggest?
The following article should help answers about nonchemical fungicides: https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm
This article should help with pruning: https://www.gardeningknowhow.com/ornamental/shrubs/weigela/pruning-weigela.htm
And, since wigelias are decidious, the diseased lookingj leaves could just be ready to fall off. If you think or know it is a disease, spray with neem oil anyway. Gather (rake) the leaves, place them in a plastic bag and put in landfill. Do NOT compost or burn diseased leaves, composting will not kill it and burning will spread it.
I need step by step instructions for pruning weigela.
The following article has all the information on trimming your weigela: https://www.gardeningknowhow.com/ornamental/shrubs/weigela/pruning-weigela.htm
What could be happening to one of my Weigela bushes. I have two bushes that are about three years old. This year was their best year for blooming, but now one of the bushes seems to be stressed. The leaves are turning and it isn't adding new growth. They are close enough to one another that the conditions should be the same. We have had a good bit of rain but they are on the side of a hill so drainage should not be a problem. Thanks, Fletcher
Fletcher, it sounds as if one of the plants is "pitching a fit"! As you state, close proximity, adequate rain and drainage... All things considered, they should both be doing will. Maybe this article can help: https://www.gardeningknowhow.com/ornamental/shrubs/weigela/growing-weigela.htm
Fall trimming. Can I do a major cut off? One new long stem , do I cut it?
This article should answer your question: https://www.gardeningknowhow.com/ornamental/shrubs/weigela/pruning-weigela.htm