I have cut it back to remove dead wood.
It's hard to tell from the photo, but you can lightly scratch a bit of the bark. If it's green underneath the outer layer, it is probably fine and waiting for the right time to spring to life. If it's dry and breaks easily, you may have lost your plant. Here's an article about pruning bougainvillea: https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/pruning-bougainvilleas.htm
If I give it a couple of litres of water, it will last for 4 or 5 days before it starts to wilt. With less water less days, the flowers do not seem to last with more water. Is there a happy medium?
It really depends on what kind of soil it's planted in. If your soil drains easily and does not hold moisture, it may need a bit more watering. But the key is to water the roots deeply, then let the soil dry out before watering it again. You may want to use a moisture meter to make sure you're not overwatering it. Here's an article for you:
https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/bougainvillea-garden-care.htm
I think the question is complete. I am asking if I should remove the bands that are holding the vines together.
I would remove them. It must be a packaging aid.
https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/bougainvillea-in-containers.htm
So I got this plant at a garden sale in Austin and I was blown away by the beautiful bright red colors ? ❤️ but not long after bringing my plant home (mind it was a hanging Bougainvillea plant ) and all the flowers fell off and it's all green leaves and no flowers ? ? what did I do wrong ?!?
The bracts will fall off but you may have hastened their drop with the environment change. Did you hang it outside in the sun? It needs light, water and fertilizer to bloom.
Here are its cultural needs to follow:
https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/bougainvillea-in-containers.htm
https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/bougainvillea-pruning.htm
https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/bougainvillea-flower-drop.htm
https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/bougainvillea-winter-care.htm
A pot plant for her apartment. She says it has lot of sunlight from glass windows
They are beautiful plants when in bloom! They do have thorns and can get rather wieldy! She needs to have a lot of space for it near a south facing window.
You can buy one from a reputable online dealer and change the delivery address to hers.
Or you can call nurseries near her and buy one for her over the phone that she could pick up.
We don't sell any plants here, we provide free gardening information.
https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/bougainvillea-in-containers.htm
I'm sorry, we do not sell plants. We only offer information on their care.
I can tell you that they will grow in container, and with attentive, proper care can do fine indoors. You may have to supplement light should there not be enough, though.
Here is an article to help care for them in container:
https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/bougainvillea-in-containers.htm
We are following your instructions but the plant is loosing flowers and leaves. There is plenty of advice for flower drop which we think we have mastered but.... The leaves still keep yellowing and the drop off. Could we have some advice please many thanks. Sandra.
Make sure you are not overwatering. Soil should be slightly dry before watering again. And they need plenty of sun. Do you have it inside or outside? They prefer to be outside, except when the temp drops below freezing. Their natural habitat is tropical areas of intense heat and low rainfall.
They are heavy feeders so either use a balanced (10-10-10) water soluble fertilizer regularly or a slow-release fertilizer twice a season.
https://gardeningsolutions.ifas.ufl.edu/plants/ornamentals/bougainvillea.html
I live on the west coast and would like to know how to care for it.
Is yours planted outside or in a pot? Here are instructions for both:
https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/bougainvillea-garden-care.htm
https://www.gardeningknowhow.com/ornamental/vines/bougainvillea/bougainvillea-in-containers.htm