How long has it been outside and did you aclimatize it before you planted it outside? If you didn't then the old leaves will naturally react that way to sunlight.

Did you over winter it in a pot, and keep it in the same pot? Maybe it is root bound and needs the roots loosened and repotted. When a plant is root bound, the roots hit bottom and go round and round and the plant can't take up the nutrients it needs to grow, so loosen and untangle the roots before you transplant.

If it gets too leggy and too few leaves and if the stems are sparse do some cutting back. That will bush out the plant with new shoots and leaves. You can root the cuttings if you want.

Thanks, oilpainter, for info on ivy geranium. I did cut plant back some, & started new cuttings. The plants are looking a bit better. We've had some rain, & it feels more like summer out there these days. It was a cold spring here. Should improve now ! Hope things are going well for you too.