I've also just thought, that you could try chucking over some
Nasturtium (Tropaeolum majus) in March - May. Yellow, orange and
red
coloured flowers (amonst others). They are pretty vigorous and
should
self seed quite freely.

I really deprecate this "chuck them over" policy. It just isn't going
to work any more than "chuck it and chance it" will catch you a creel
of trout.

I beg to differ. How do the seeds of your plants get from the flower heads
to the soil? Mine fall, and wouldn't know the difference between falling
from a hand and falling from a seed pod.

Cheers

Nick
http://www.ukgardening.co.uk