2 artificial plant arrangements (Stirling FK8)

The main artificial plants in the plastic terracotta pots are ferns. The square and circular plastic pots are both approx 27cm in width. The arrangements are approx 40 cm in height. The plants are secured in a mix of holes in a large yoghurt pot and small stones. I have had the pots out in the balcony for months, sometimes in windy weather and none of the plants have come loose. The pots could do with some drainage holes drilled in the base so that they don't fill up with water in wet weather. I can't do this, as it will cause dripping onto the balcony of the neighbour below, that's why I am looking for a new home for the plants.