Shallow planting advice.
My front garden was mud and weeds. I have cleared the weeds/wild flowers and put down a layer of terram and gravel. To break it up a bit I have built a circular bed. I will plant it up next year properly but for now I want to put bedding plants ( bizzy lizzie, begonias, marigolds ect) for instant colour. I only have about 60mm planting depth though as I don't want to split the terram until the spring so it has a chance to suppress what's under it. Is this enough depth for my planting or has anybody got advice for shallow rooted plants ?