Posted: 11/03/2015 at 15:13
I am the biggest threat to everything in the garden as I am always moving or shifting plants.
Lupins should be the easiest out of all the perennials mentioned. They come back from root and self seed freely. They like full sun and well draining soil. Delphinium and Holyhock are also easy from bare roots though the latter tends to get rust for me.
Rudbeckia I struggle with. I have grown them from seed and I can see them come up the next year but they never seem to flower.
Kniphofia are a challenge for me. Apart from the evergreen Northiae mine seem to dieback and they are in a sunny south facing position with grit and protection. I have seen slugs attack the stalks have way up and me lose flowers that way .