Making a False Bottom for Large Garden Planters??

[Juliand]

Another random one for you....
I've bought some large deep garden planters, 900 mm high by 800 wide and 300 deep X 5, plus another 5 slightly smaller, ten in total....so an awful lot of  compost. Hence the thought of putting in a false bottom so that I'm only putting compost in at about a foot or so deep....

But, what can I use to make the false bottom?

Was thinking  MDF but I suppose that will just soak up the water. Any thoughts, please? Just called up a local timber mill and he was flipping useless.

Plywood sealed along the edges, maybe?? Wrapped in bin liners? Some bright boys on here, so someone please? 

Cheers

[pudding]

It's normal practice to just put a load of medium stones at the bottom of the planters for drainage.   That will reduce the compost volume!

Putting bits of wood and plastic in there to reduce the volume sounds counter productive?  You may as well buy smaller planters?

[Juliand]

It's normal practice to just put a load of medium stones at the bottom of the planters for drainage.   That will reduce the compost volume!

Putting bits of wood and plastic in there to reduce the volume sounds counter productive?  You may as well buy smaller planters?

Thing is wifey will want them moving 6 times before deciding they're in the right place, and they're already mighty heavy.....

[pudding]

It's normal practice to just put a load of medium stones at the bottom of the planters for drainage.   That will reduce the compost volume!

Putting bits of wood and plastic in there to reduce the volume sounds counter productive?  You may as well buy smaller planters?

Thing is wifey will want them moving 6 times before deciding they're in the right place, and they're already mighty heavy.....

I move my big pots around the garden with a sack barrow, or borrow a mate or two to help shift them.  Or just put your foot down with the missus and tell her to choose a spot and stick with it 

[willni]

Yep gravel stones is the common practice, annoying to move. You could also get some good timber and cut it up into chunks and char it. The char acts as a natural anti-rot, a bit of a lighter option.

Orrr make a raised platform as you'd like and wrap it in damp proof membrane staple it at the top then place another piece on top unstapled down and this will  give you a waterproofed platform.

[garrardrj]

Use polystyrene to fill out large pots.

[grey golfster]

Use polystyrene to fill out large pots.

+1. That's what I do.

Ideally large expanded polystyrene blocks, like from around a new telly or similar.
Also helps to reduce frost damage to the planter, not​ so much wet compost to freeze.

[Juliand]

Thanks for all suggestions. I did think about polystyrene. It's having it when you need it! Comes in bulk with TV's etc, no where to store it, so you dispose of it, doh! Wonder if Curry's might have some??

Reminds me of something my dad used to say, bless him,  "You never know when it might come in handy". Probably why I'm such a hoarder by nature, but after a few house moves, I'm becoming more "just buy it when you need it". I've spent hours in the past searching for some item that I knew I had somewhere - could have just gone and bought it afresh in much less time and frustration, ha ha. Lessons in life, eh!

[grey golfster]

I've just dumped some polysty from around a new dishwasher.....ideal.

Try your dump/tip...sorry, I mean household Recycling centre 
Or in the skips around the back of Currys/PCW/Argos etc...
Hours of fun!