Sleeper planter bench

[jimmbo]

Hi

I’ve built a sleeper planter bench and I’m wondering how best to fill the planters.
I’ve currently got a mound of clay soil/rubble etc which I dug up before laying my patio and I was thinking of dumping some of it back into my planter boxes before putting a good layer of top soil on top.
I realise the clay soil isn’t great for drainage but mixed with rubble and some leftover gravel I can’t see it being a problem. But how much space should I leave for the topsoil? The internal dimensions for the planters are 600mm x 400mm x 800mm deep.
Thanks

I’ve no idea what’s going in the planters yet btw!

 

[sodthisforfun]

Knowing what you're going to put in the plants would help - and how big the root system is going to be. If it's seasonal flowers that you put in every summer, then fine, you'll not need too deep soil. If it's something heftier then I'd put just a small layer of stone on the bottom for drainage and put in a mix of topsoil and compost. Top soil isn't the best for pots as a golden rule and personally I wouldn't use it in the pots at all.

Nice bench, very rustic!

 

[lostinthelight]

To minimize any future rot in your handiwork I would be inclined to fit the largest pot that will fit or a series of smaller pots that will occupy the space and plant in those . This would give the option if varying your planting/options without any loss of flowering time and any tender plants can easily be moved, should work until you had found what suited ?

 

[jimmbo]

Thanks for your replies.

I have fitted some leftover damp proof membrane around the internal sides of the planter boxes so the sleepers aren’t in contact with wet soil.
There is nothing on the bottoms - just the existing clay soil underneath.

So far I have placed some large stones/rubble in the bottom to help with drainage. My plan was to then fill them to say 2/3 full with the excess clay soil/gravel that I excavated and fill the top third with top soil/compost? (I’ve no idea about gardening!)

We were thinking some sort of evergreen shrubbery and plants/flowers that don’t need too much maintenance (if any)!

Thanks

 

[sodthisforfun]

If going for shrubs, I'd certainly not put so much rubbish back in the boxes - fill them with good quality soil. Plants with healthy roots (and room/nutrients to grow those roots) are happier plants!

"So when is topsoil not ideal? Well, if you’re growing plants in pots, you’ll probably find that topsoil doesn’t really provide enough nutrients. It’s fine where the plants can spread their roots and reach out for more nutrients, but when they’re confined to a pot, it’s not so good."

https://www.topsoilshop.co.uk/topsoil-vs-compost-when-to-use-what