John Innes Potting Soil Recipe

John
Innes Potting Compost

JI #1 Base

7 parts sterilized loam

3 parts peat

2 parts sand or grit

Fertilizer: 4 oz / 8 gallons (3 grams / liter)

Lime or chalk: 3/4 oz / 8 gallons ( 0.5 grams
/ liter)

JI #2 Base: Same as 1 but double the Fertilizer
and chalk
JI #3 Base: Same as 1 but triple the Fertilizer
and chalk

JI Seed compost: The fresher
the sterilization, the better the germination

2 parts sterilized loam

1 part moss peat

1 part sharp sand

The loam and peat is put through
in 3/8 in (9mm) sieve.

To each bushel or 8gal(36 L) is added:

1-2 oz (42gm) superphosphate

1/2 oz Potassium nitrate

4-6 oz (21gm) ground limestone

Ericaceous Mix: Use the base
but leave out the Lime

Soilless: 3 parts peat and
1 part sand

Potting Compost: (same as above)

7 parts sterilized loam

3 parts moss peat

2 parts sharp sand

The loam and peat is put through
a 3/8 in (9mm) sieve.
To each bushel (8gal/36l) is added

3/4oz (21gm) ground limestone

4oz (110gm) 14-14-14 Osmocote

This makes John Innes Potting Compost
No. 1.
For a richer mix simply double the quantity of

John Innes Base to make No. 2 or treble it to

make No.3