cutting grass around veggies?

Now , this morning I have spread like 80% of the seeds that I have in my seed box in the garden, based on a suggestion that I read recently on a thread (but I cannot find it) according to which if the right conditions are met they will grow. So if it all works out I should have a mix of hollyhocks, cabbages, onions, asparagus, lettuce, spinaches, canterbury bells, amarantus, cucumbers etc....

Of course I was just fed up keeping all the seeds forever in the seed box, that is the main reason, and the other reason is that nothing is happening until they are in the box in a wrapping.

But my second thought is...Should something germinate from this , how does one deal with cutting the grass? Will I just have to keep tall grass in order to see some flowers/vegetables?