West Sussex,
United Kingdom 
pelargonium geraniums.
I brought these in from the garden into the cold back porch in the autumn, where they have bloomed profusely all through the winter. I have a feeling that I'm doing something wrong. How will they keep their strength up to bloom through the summer again as well, or should I just take cuttings and if so, where should I cut them and when?
13 Mar, 2018
Answers
when you cut them back say April use the prunings to make cuttings. make sure you disbud any you want to root though. I will do mine mid/late april and keep them in the conservatory until late may early june when they will go out.
I agree about repotting too.
13 Mar, 2018
Agree with above, they will be fine. I've been doing same with mine for 5 years. You might just want to repot them with fresh new compost/potting soil before you put them out again. Yes, you can still take cuttings if you like, but mother plant should continue on like a trooper.
13 Mar, 2018
Well, that's a relief. I had worried that perhaps I should have been removing the blooms during the winter so that the plants could rest, but they made such a wonderful splash of colour through the dark, dull days that I couldn't do it! Thanks for the advice, everyone.
13 Mar, 2018
They'll be fine. They are just responding to the conditions they find themselves in.
I would repot them, and cut them back if they get leggy. They'll get 'strength' i.e. nutrients from the fresh compost.
13 Mar, 2018