Alpine trough - tea towel?

AnniD

Following Monty's planting of an alpine trough a couple of weeks ago, l thought l'd do the same.
I know he had a layer of grit on the bottom and then place an old tea towel over the top to "stop the soil mixing with the grit".
He then planted it up using a 50/50 mix of grit and compost. 
I have an old tea towel, so no problem there, but l have been looking at other videos on line and basically they all just plant straight into the grit/compost mix.
Just wondered if any forum members have an opinion before l begin? 
Many thanks 

Fairygirl

I can't see the point personally. You're using a mix of grit and soil, or compost, anyway, so why bother separating.
I could see the point of using a layer of fabric to prevent the mix blocking the drainage holes. I do that using old scraps of landscape fabric, or even face/baby wipes, as it also saves taking up a lot of space in a small or shallow pot. 

AnniD

Thanks @Fairygirl, l have covered the drainage hole. I went back to watch Monty doing his again and thought it seemed a bit counter productive, if you see what l mean .

Fairygirl

Makes no real sense to me either. I don't watch it, but from your description, I can't see any point at all 

wild edges

I've tried something similar with green roof planting because the wider the area you're covering the more water can be stored. You also don't get the same gravity pull through the soil when it's very shallow. Basically if you pour a litre of water that weighs 1kg into a tall, narrow pot the weight of the water draws it down to the lower levels but if you spread the same water around a wider area it sort of floats in there. Water can rise back up in soil to a certain height by capillary action but with deeper soil it has to fight gravity to get to the higher levels. With shallow soil it can stay very wet without a clean drainage layer to prevent that ponding at the bottom. In the summer though it rarely matters so you're just dealing with winter wet and if you can put your trough somewhere sheltered or give it a roof somehow then all that drainage stuff is just overkill. Monty's troughs stay exposed all year and he gets a lot of rain so his technique is sensible for him. I put all my troughs into cold frames in the winter and save myself the faff of all that extra drainage. It makes the troughs easier to manage in summer without it too as you don't need to be watering daily just to keep the roots cool.

Fairygirl

That makes sense @wild edges, but as you say - why not just put them somewhere sheltered over winter.
I do that with pots which have succulents in them, or I just tip them on their sides a bit. Have never lost one, and we certainly aren't short of wet stuff here.
Probably wouldn't be so easy with a big trough, but a simple shelter, or even a couple of bricks at one side to get them angled would probably suffice if the soil medium has sharp enough drainage.

AnniD

Well, it's planted up now minus the tea towel, but l'm able to cover it with a sheet of plastic and bricks combo come the Winter.
There's no way l can move it even if l wanted to. It weighed a ton when it was empty and was manoeuvred into place with the aid of a sack trolley. 
Thanks for your comments