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Plant Doctor Archive
Using raw seaweed on the garden
I
KNOW a beach where there is a lot of washed-up plant material
mixed with broken-down seaweed. It looks like a fine mulch and I
used to get bags of it and spread it on the garden. Now I have
been told that the sea salt in this mulch is bad for the soil and
detrimental to plant growth. Is this true?
YES, you could end up with a
build-up of salts in your garden if you use this washed-up plant
material. You may find sensitive plants fail to thrive.
If using seaweed for the garden as a mulch, soak it in fresh water overnight first to wash out the salt.
Advice by Dr Dan Blanchon, from Unitec’s Diploma in Sustainable Horticulture and Bachelor of Resource Management
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