John Innes Composts

Commonly known as John Innes Composts, the essence of these composts from today's point of view is that they are based on loam. There are several formulae, depending on the use of the compost: JI KOK◊„«ÚAPP Compost is for sowing seeds; JI Cutting Compost is for rooting cuttings; JI No 1 Potting Compost is for pricking out young plants; JI No 2 Potting Compost is for potting on; JI No 3 Potting Compost is for established plants and shrubs; and JI Ericaceous Compost is for plants which cannot tolerate lime.

In these tables, = loam, = peat, and = sand. All parts are by volume.

JOHN INNES SEED COMPOST:


To each cubic metre of mix, add

0.6kg ground limestone
1.2kg superphosphate


JOHN INNES CUTTING COMPOST:


No added fertiliser

JOHN INNES POTTING COMPOST:


For JIP-1, to each cubic metre of mix, add

0.6kg ground limestone
1.2kg hoof and horn meal
1.2kg superphosphate
0.6kg potassium sulphate

For JIP-2, to each cubic metre of mix, add

0.6kg ground limestone
2.4kg hoof and horn meal
2.4kg superphosphate
1.2kg potassium sulphate

For JIP-3, to each cubic metre of mix, add

0.6kg ground limestone
3.6kg hoof and horn meal
3.6kg superphosphate
1.8kg potassium sulphate


JOHN INNES ERICACEOUS COMPOST:


To each cubic metre of mix, add

0.6kg flowers of sulphur
1.2kg superphosphate

The quality of John Innes Compost will vary according to the quality of loam used, and also to the length of time it has been stored. Composts with higher levels of fertiliser will degrade faster than those with less fertiliser. Ideally, compost should be mixed as soon as possible before use, or used as soon as possible after purchase.

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