I have found they germinate easily if you use fresh seed, but not good results with old seed.
I bought a small weed burner, wasn't very successful. Killed the top growth, but not the roots, weeds grew back.
I grew most of those last year and French marigolds and Lavatera Silver Cup, but there were still weeds. It will need weeding, I expect, whatever you do.
I wanted to know the answer to this too. I had an asparagus plot and it got over run with bindwind that I couldn't dig out because of the asparagus roots. Gave up in the end. But the asparagus was better than any I'd bought.
Even if static and lined?
Sunny and cold so far.
When digging heavy soil I find a fork easier.
I always water with rain water as I have hard tap water.
Strobilanthes anisophyllus "Brunetthy
This is one from Google.