I have a plumbago planted in my yard in Union City, TN. How do I care for it through the winter?
You are right on the edge of where this plant can survive. I would recommend mulching heavily around the base of the plant. It should survive a typical winter where you live, but if you have a cold winter, it most likely will not. For future reference, plants that are border hardy in your area (like this one) should be planted near foundations or in created microclimates in your yard (https://www.gardeningknowhow.com/garden-how-to/projects/how-to-make-a-microclimate.htm) to give them a better chance to make it through cold winters.
If I plant a plumbago next to the fence in my backyard, how far away from the fence should I put it?
I would give it about 3-4 feet of space between the fence and plant, as it needs plenty of room to grow. Here is more info for growing, if you have not already seen it: https://www.gardeningknowhow.com/ornamental/shrubs/plumbago/growing-plumbago-plants.htm
I have a specimen plumbago that was in full bloom and overnight appears to be dead. No flowers or leaves, just dried sticks of a plant.
Will it come back if I prune it or is it gone? I hate losing it if it will revive. Any reason this happened?
This article will help you determine if it is still alive and worth trying to save:
https://www.gardeningknowhow.com/plant-problems/environmental/how-to-tell-if-a-plant-is-dead-and-how-to-recover-an-almost-dead-plant.htm
As far as to why, there are many, many things that can kill a plant. For as quickly as you describe it succumbing, I would lean towards a chemical herbicide. Sometimes if someone is using something like Roundup on a windy day, the overspray can hit unintended plants and kill them.
I live in central/south Texas and would like to try to grow plumbago from clippings, if possible.
You can grow them from cuttings. Here is more information that should help: https://www.gardeningknowhow.com/ornamental/shrubs/plumbago/growing-plumbago-plants.htm
https://www.gardeningknowhow.com/ornamental/trees/tgen/how-to-root-cuttings-from-various-shrubs-bushes-and-trees.htm
I live in FL, zone 9. Why do my plumbagos have dark brown leaves in the joints of the branches? How often should I fertilize? I have very sandy soil but put rocks in the bottom of the hole before I planted and use black cow fertilizer on the surface and every 30 days or so use Miracle Gro. Is that right?
The dark leaves could be natural coloration, if the leaves are supple and healthy otherwise. If they are dried out, then it might be a fungus. A standard fungicide will treat that.
As far as the fertilizer, the Black Kow is fine every month. If you are using Miracle Gro, I would do it once every 2-3 months as it is a bit more potent.
I live in Boca Raton, Fl. and four of my plumbago died. They were in good sized pots and were flowering beautifully, but surprisingly all died at the same time, planted in different locations. It is hot here, and we are having a lot of rain. Can you tell me why they died? Thanks,
Gloria
This article might offer answers: https://www.gardeningknowhow.com/ornamental/shrubs/plumbago/growing-plumbago-plants.htm
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