Free Draining Compost - Large Containers

TerrysWorld

Last year I planted a Torbay Palm in a large container with John Innes No3 and grit (50/50).

This stayed out throught the winter and is water logged dispite the mix, crockery at the base and raised on feet.

I have Canna's and Banana plants to put out in containers with fresh compost.

Not wanting to have water logged compost again.

Any advice for these plants. thanks

celcius_kkw

I have had major issue John Innes 3  as well to be honest. I have tried westland and some other lesser known brands but all had the same drainage issue. One of my climbing roses in a very large pot was essentially drowning throughout winter - I had to repot it (which is no small task given the amount of compost the massive pot holds)

Since then I have changed my potting mix recipe to 20% John Innes 2, 40% multipurpose compost, 30% grit and 10% perlite. I feel that John Innes no2 has a less compact texture - no3 sometimes feel almost like topsoil!

I also add a good layer or slate/large pebbles at the bottom and drilled larger holes in all of my pots (even if they came with drainage holes already)

That seemed to have done trick and none of my plants are water logged anymore

JennyJ

JI no 1, 2 and 3 are all supposed to be 7 parts loam, 3 parts peat and 2 parts sand, it's just the amount of added nutrients that differs.

https://www.gardeningdata.co.uk/soil/john_innes/john_innes.php

BUT, I've also found that no. 2 seems less claggy than no. 3, so maybe not all suppliers follow the recipe exactly. Maybe some use coarser sand, or maybe the loam differs (I don't always get the same brand).

TerrysWorld

Thanks,
I have approx 40m layer of surface grit.
Water appears not to flood in a rain storm around the brim, it seems to be draining but its just so wet.

Borderline

Either you need more coarser grit but mix in multi-purpose compost, especially near the top few inches of your pots. This should help open up the texture. Always keep the containers raised off the ground in the winter months.