Using garden soil instead of John Innes 3 in pots

andy1977

I have some David Austin bare root roses that I need to plant in pots (large containers).

They recommend a mix of JI3 and multi purpose compost.

However as this is fairly expensive and difficult to source at times, can ordinary garden soil be mixed with multi purpose compost in containers?

Thanks 

Plantminded

As roses need fairly rich soil to flower well, especially in a container, I'd go with the recommended JI3 and MPC mix.  Garden soil can be lacking in essential nutrients unless it has been well conditioned or mulched.  If you can't get JI3, some MPC brands like Levington include it in their mix. 

Dovefromabove

During lockdown when I couldn’t get JI3 I used a mixture of garden soil and MPC with the addition of some FB&B.  It was sort of ok … except for the very healthy crop of chickweed now in my containers 🙄 

rossdriscoll13

You shouldn’t use garden soil in containers as it lack the necessary drainage to allow plants to grow properly in pots.  Either use, as DA say John Innes No 3 mixed with multi purpose compost or you can buy compost especially for roses.  I use Westland Rose and potting mix which is very good.

JennyJ

I sometimes mix garden soil with mpc for containers if I want some weight and better drainage without extra nutrients, eg for lavender or shrubby salvias, but mine is very sandy and gritty so it's more like adding sharp sand with a bit of organic matter. I don't think I'd use it for roses, they want something richer.

punkdoc

MPC + garden soil  should be fine.

Allotment Boy

Remember John innes is a recepie  of loam (soil) MPC,  grit, sand  and fertiliser in various proportions. They are available on line. So you could mix your own but you would need all the ingredients.  Unless you need a lot it's probably cheaper to buy it ready made. 
Certainly garden sil would need grit to stop it compacting and extra feed.

Dovefromabove

😊 that rather depends on the garden soil @Allotment Boy … here it’s already more like gritty sand 😂 

Busy-Lizzie

I have used garden soil mixed with compost (MPC) and rotted horse manure with a bit of blood, fish and bone for roses. To prevent weeds I used MPC for the top third. It worked very well in large pots.

Fairygirl

Garden soil is fine if it's a decent quality. The only problem is that not all garden soil is decent, so if it's sandy, chalky, very, very gritty, or very wet and compacted, that would be a problem.
However, it's easy enough to amend it for pots by adding compost, or organic matter of almost any kind,  and/or grit, depending on the quality of that soil. 
JI is just a mix - a recipe/formula, as said 

Marlorena

It depends.  If the garden soil is in hearty condition, a good loam, and not dense heavy clay, then you can use it with a good quality MPC, but there are some things the member needs to be aware of ..
They should not use soil where other roses have been grown, nor Pyracanthas, Apples, Rowans etc..  as the soil may be contaminated.
A sprinkling of mycorrhizal fungi over the roots [extra expense] is recommended if using garden soil to that extent..

Better results will be obtained using the JI3/MPC mix, so if you are prepared for a lesser result, that's ok, but the purpose of growing in pots is to achieve maximum output as they tend to be placed in display/patio areas..

Also, David Austin English shrub roses are gross feeders and water guzzlers.  You need to be prepared for that as neglect will not do..   

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