I have a border at the front of our house that I need plants for. The soil is clay, there's lawn on one side of the border, pavement on the other side - no walls, only slightly shaded at one end of the border. We had Hebe in there but it hasn't thrived - we think the soil isn't well drained enough for it and it may have root rot. We've dug the Hebe out and need something to replace it. Any suggestions for what might do well there??