Q.Taxus or knockout roses
I have a long narrow planter that is under the over-hang of the house. For years there were taxus planted there with no problem. They got very little water only from rain and then morning sun. I took them all out several years ago due to age; they were only about 2 ft tall. Nothing will grow there. Purchased daylilies that did nothing. Should I put taxus back in? The old ones were shaped into a long rectangle box, which I did not like. I love knockout roses but don’t know if they will get enough water. Appreciate your help.
I would start with replenishing and amending the soil in the planter.
It is likely in need of some organic material to provide the necessary nutrients for plant success.
Knockout Roses would not be a good choice for your shaded area.
They would need a full sun location.
Here is a link with more information.
If you had success with Taxus Yew shrubs you certainly could replant. Perhaps a new variety that may give you new look. Sunburst is a spectacular variety.
Here is more information.
Here are some more articles on shade loving plants.