Mushroom compost

LauraEllen

Hi there
Am looking to bulk buy some peat free compost. Many companies seem to sell Mushroom Compost. I want this to grow shrubs and plants in is it ok to use? 

Thank you 

Fairygirl

Mushroom composts tend to be alkaline, so it would depend what plants it's being used for.

Pete.8

I buy a bulk load every couple of years and it is as @Fairygirl mentions quite alkaline - you can often see bits of chalk in it so it may not suit your plants/soil.

My soil is slightly acidic and I've not had any problems using it.
I've bought mine bagged from CPA Horticulture and I do find that it is quite 'hot' when delivered and with a hint of ammonia (it contains poultry manure) so I stack it for a few weeks to let it cool down and let the urea break down before using it.
But for my soil it works very well.
I spread it in mid-late winter too before any growth appears so there's less chance of burning any plants.

LauraEllen

It's for my clay soil, just to plant things like salvia and pittosporum... Is well rotted manure better?!
Thank you !
No idea here

Fairygirl

Clay soil isn't great for salvias unless it's very open and well draining. Salvias need sun and free draining, poorer soil. They aren't terribly hardy in many areas either.
Pittosporums are less fussy. 
There's a very good motto - right plant, right place. If you can't provide the right conditions, you need to plant accordingly. Improving clay can take a long time, and well rotted manure is the best choice for opening it up, and improving drainage. 

Pete.8

I had building works done in 2019 and LOTS of orange and grey clay was dumped in the front garden where I wanted to plant a row of 12 pittosporum Golf Ball.
I bought lots of composted bark fines (as recommended by RHS) and dug that in over winter. By late Spring I was surprised that the heavy clay soil was already transformed.
I dug in a few bags of mushroom compost and planted the pittosporums - they have grown very well so far and seem happy there.

My soil is clay and I do grow plenty of salvias in a mild Essex climate and in sunny parts of the garden, but I have been improving the soil with manure and compost over many years - so it can be done once the soil drains well and isn't claggy.

LauraEllen

Thanks @Fairygirl and @Pete.8 I do wonder if the spot I wanted the salvia in is sunny enough. My soil isn't heavy clay and is quite stony. 
Sounds like I need to improve it! 

Pete.8

I had Salvia Amistad growing amongst tall shrubs and under the canopy of an elaeagnus quicksilver and it was very happy there for several years.
Sadly the slugs got it last year....
Stony ground will suit them and as long as they get some sun you should be ok.
Try one or two - cuttings are very easy and grow fast so you could soon have plenty

LauraEllen

Thanks @Pete.8 for the tips, Just looked up elaeagnus quicksilver which is very nice looking too!

zugenie

I grew a number of salvias in clay soil that had compost mixed in the first year

Fairygirl

It's more about drainage and climate for Salvias, and not just climate in summer when they're mostly flowering. 
Nothing wrong with clay, but if it's not improved, and you live in a colder, wetter area, that makes a huge difference. They don't survive year to year here because even with a good site and adequate drainage, they can't manage our winters - even 'mild' ones. Many areas have the same problem. Possibly they would have this year - mildest driest I can ever remember.

If I wanted them, I'd either need to pot them, and overwinter in a greenhouse, or take cuttings. I only grow the totally hardy one - S. caradonna. Plenty of other similar plants which are hardy though, so it's not a problem