In answer to your question about the hardiness of geraniums...
Diane DeRienzo writes:
I have hanging pots with geraniums that are still blooming beautiful flowers.It's getting down in the 30's at night so I've been bringing them in and out. What should I do to keep them from dying over the winter? Should I let them dry out or bring them inside?
So many people love these versatile and friendly plants:
Geraniums (properly named Pelargoniums – but we all tend to stick to ‘geraniums’, much easier!) come originally from the dry, sunny upland areas of South Africa, which is why they revel in the sun and never seem to mind how hot it gets.
Like many similar plants they can tolerate a degree of cold much more easily than damp, in fact in rainy times they cease to flower and grow green and soft.
I take my pots indoors when the later autumn becomes both cold and rainy – not that they are grateful, they sulk and lose quite a few leaves because they are unhappy away from the light.
You can do what many people find very satisfactory, which is to allow the pots or hanging baskets to become fairly dry and then to trim off all soft growth (cut stalks just above the lowest pair or pairs of leaves) and make sure there are no dying leaves or stalks lying on the compost (which could spread rot).
Keep them in a dark cool place for the winter, and then bring them out when spring is well under way.
They will start into growth quite quickly and all you will need to do is feed (and possibly re-pot) them to have an even better show of flowers in the summer.
I do this with a huge pot of semi-hardy fuchsias and they have flowered well for me for about four summers now.
One final point – it is well worthwhile taking cuttings from geraniums or fuchsias that you love and it’s extremely easy.
Early to mid summer cut off side shoots about three to four inches long, pinch off any flowers and press two or three cuttings into a five inch pot of gritty, barely damp compost.
Place the little pot or pots somewhere shady, give them just a little water from time to time and in six or eight weeks you should see tiny new leaves appearing - this is very good insurance!