Posted: 31/01/2014 at 13:09
The plants you are considering do like very well-drained soil, preferably not heavy clay. I have tried (and failed!) planting them in heavy clay, unless I raised my borders to improve drainage and added loads of grit, light topsoil and bark chips.
This seemed to the trick for me, soil-wise.
Apart from Verbena B., which can grow 6 ft in one season and acts as a brilliant annual filler, the others (bar echinacea, which I know little about), as slow-growing and can be well-contained by cutting back, so in other words are not plants that will invade or grow out of control.
It's good to leave some space in between, when planting, and you can always fill gaps with small annuals until your other plants have grown in.
Maybe stick some bulbs in there too - sternbergia crocuses (bright egg yolk yellow) look fab growing out in between perennials and love sun - they'll come out in Autumn and self-colonise.
be aware though - many of the plants you've selected hate being overly wet and cold over the Winter - I have lost many due to that, and due to planting at ground level in clay.
I find they do best in pots, where I can control the environment for them better.
have a think about adding height to your border too and possibly a feature.
Have a look at this for some planting ideas and above all, don't be afraid of moving things and making mistakes - we all do and it's part of the fun and the process