Q.Recommended Hardy Flower/shrub For Large Pot
I am looking for a HARDY flowering tree (that grows to approx 4 or 5 feet tall) that will grow in a large pot on my front garden. I previously had an oleander but the frost has got to it as I didn’t realise it was not hardy.

Certified GKH Gardening Expert
You could try a shrub rose such as a Knock Out, which are hardy and bloom all summer. Hydrangeas are very popular, and some take more sun than others and they come in varying heights. A rose of Sharon can be grown in a large container and will bloom most of the summer.
https://www.gardeningknowhow.com/ornamental/shrubs/rose-of-sharon/rose-of-sharon-bush.htm
https://www.gardeningknowhow.com/ornamental/flowers/knockout-roses/potted-knock-out-rose-care.htm
https://hgic.clemson.edu/factsheet/hydrangea/