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Possible compost problem
I have 2 Gardenia jasminoides which the RHS suggests prefers a neutral or acid soil. One I planted in a pot in Westland John Innes ericaceous compost, the other in the garden which is neutral on clay in Essex
The one in garden soil has struggled a bit but but the potted one is doing reasonably well, however, the compost seems a bit 'stodgy' to me and not particularly free-draining. Is this usually the case, or should I add a bit of sand to improve this?
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I add grit at a ratio of 4 parts JI no 3 to 1 part horticultural grit for most container grown shrubs ... If I have some available I add some leaf mould too.
I don't see any reason why that won't work with ericaceous compost too.
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.
I agree, some of the loam-based ericaceous composts are a lot heavier than compost-based ones so adding about 20% grit is a good idea. You could always mix it with some compost-based ericaceous to lighten it too. I lost a couple of blueberries to root rot over the winter a few years ago when they were planted in a JI formula ericaceous which had become waterlogged even though the drain holes were clear. I mixed it with with a compost-based ericaceous, composted bark and some grit, planted new blueberries and they are thriving.
Thanks for both replies, I will try adding some grit as suggested.
The information about compost-based ericaceous is useful as it was not something I had thought about.