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well rotten manure or multipurpose
Lockdowngardner
Posts: 19
in Plants
Hi all
Im about to repot my potted perennials and according to the information on the RHS website some of my plants require humus rich soil. My perennials will be in John Innes #3 but do I add well rotten manure or multipurpose compost to have a good humus content.
Im about to repot my potted perennials and according to the information on the RHS website some of my plants require humus rich soil. My perennials will be in John Innes #3 but do I add well rotten manure or multipurpose compost to have a good humus content.
AmateurLiz
0
Posts
i only add humus if the rhs plant details recommend it. Don’t believe John innes 3 contains humus
Home-made compost is also humus-rich.
JI and MPC are not humus-rich products.
A mix of JI3 (about 60%) and MPC (40%) will be fine for your perennials.
If you can also add some rotted manure and grit too, that will improve the mix further.
Billericay - Essex
Knowledge is knowing that a tomato is a fruit.
Wisdom is not putting it in a fruit salad.
I think when people refer to 'humus rich soil' they are usually actually meaning soil with lots of organic matter. Dark, crumbly and well rotted; like woodland soil. Generally plants requiring these conditions will be woodlanders.
In your context I would just add MPC to the JI3 or topsoil as Pete describes, which will open up the soil structure and add some of that nice organic matter that helps roots penetrate through the soil, and holds on to nutrients. For ericaceous plants, use ericaceous compost. I would stay away from manure as it contains a lot of nutrients and might cause problems with some plants. For 'Mediterranean' plants you might want to add lots of grit instead of or as well as the MPC.