Posted: 12/02/2015 at 21:38
Cassie, tip them out of the pot, you'll soon see if they're pot bound the roots will be all around the sides. One size bigger is fine for another year. Tease the roots out and pot up with a suitable compost, John Innes No3 is the best. As for the rose, most roses had black spot last year, I treated fifty or more in the gardens I look after. With potted roses, I only move them up a size if they are struggling to produce flowers. I find good feeding in early spring, replacing the top inch or two with fresh compost, again John Innes No3 and giving a good feed with a rose fertilizer gets the best results. Spray with a fungicide as soon as the weather warms up spraying the whole plant AND the top of the compost. This reduces the chances of black spot. Keep it well watered and feed again after the first flush of flowers. Stressed roses are more susceptible to black spot, so if you keep on top of the feeding and watering, you'll get a good display. Inspect the roses regularly and spray again drenching the whole plant flowers and all at the first sign of any trouble, pick off any affected leaves, burn or bin them.
It's been nice and cold this winter so the chances of black spot will be reduced, hope all goes well.