Try feeding them with tomato food it may help
They are both garden weeds and the seed was probably in the compost you used.
You forgot to post the picture
I have Vinca major under my leylandii hedge. It will root wherever it touches the ground so quickly spreads. It also has flowers.
Busy-Lissie, I think you should ask for a second opinion before embarking on such a terrible treatment program
FB, I have only one dane, two would be too much
My RHS Pest & Diesease book says that sweetcorn can suffer fron Boron defieciency but doesn't explain how. Matbe worth googling it
what a coincidence, I have a great dane called Cassie
The first one is Evening Primrose and the second one is a Malva. Both self seed well
You have nothing to lose by trying. I would put the cuttings in a pot of compost to root rather than water. 5 or 6 cuttings to a pot and then put inside a poly bag to keep them moist.