Drainage Ideas For Simple Roof Planter Box

Question

I’m planning to build a simple planter box to put outside my window (on the Kitchen roof). I have concerns about how the water will drain out as it will surely drip through the box on to the roof. I have a drain pipe at the edge of the roof very close to where the planter box will sit. I’ve attached a picture of the roof, the green outline represents where the planter will sit and the blue represents where the drain pipe runs. Any tips on how to manage the drainage of the water would be much appreciated.

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Answer 1

I think a trip to the home improvement store might prove effective. Look for a lightweight drip liner with three sides and a dip to put against the edge near the rain gutter. Much like a large dish draining liner. Then set your container on that. You also may be able to fashion a liner using pond liner and gravel.

Here are some articles that might give you other ideas:

https://www.gardeningknowhow.com/special/urban/rooftop-gardening-for-city-dwellers.htm

https://www.gardeningknowhow.com/special/urban/creating-your-own-rooftop-garden.htm