Posted: 08/02/2017 at 17:32
I think a rose and a clematis would work well together, but I think Sweet Peas are best on their own. Sweet peas need thin closer together supports to climb up, like wires. My OH put up a trellis for sweet peas for me in the veg garden but they find the wood too thick for their tendrils and I have to give them extra support. Sweet peas also need regular picking to keep them coming and it's not so easy when they are wound around other plants especially roses with prickles!
I have a pale pink "The New Dawn" rose growing with a purple clematis on a stone pillar, that works well and the clematis keeps flowering when the rose has stopped.