Substrate and soil are not the same recipe
Coconut coir is not a field. Don’t copy the field bag into a bag of media.
- Bags and soil beds in one house; recipes get copied the wrong way.
- Substrate has no soil buffer; EC is jumpy.
- Soil has a buffer; a mix almost has none.
- A mix shows shortage faster, but read EC and pH first.
- Don’t pour a garden-soil recipe into coir; don’t heap manure into substrate as if it were soil.
- Leachate EC / pH: Follow the crop stage. Measure every day, or on a rhythm
- Name what you see before you feed.
- If leaves, roots and the surface disagree, stop.
What you see in the field
Bags and soil beds in one house; recipes get copied the wrong way. Substrate has no soil buffer; EC is jumpy.Walk the worst strip and compare a neighbour. Photograph the whole plant, a close-up and the soil surface. If those three do not line up, do not rush a bag. Lab numbers have to match the field.
Tap to enlarge. The caption says what to photograph. Missing field photos are marked as to-be-added.
Why it looks like this
The field looks like this because the root cannot take water or nutrients the usual way. Fix the soil condition first — drainage, salt, acidity, compaction or a salt of fertiliser — then a thin feed. Rates live in the range on this page; confirm with a local station and the label.
Easy to mix up
Looks like “Soil culture”
Soil has a buffer; a mix almost has none.
Looks like “Nutrient shortage”
A mix shows shortage faster, but read EC and pH first.
Do this / don’t do that
- 1Bags and soil beds in one house; recipes get copied the wrong way. Substrate has no soil buffer; EC is jumpy.
- 2Two files. Test EC and pH more often in substrate. Read the leachate. Don’t pour soil-manure habits into a bag.
- 3Don’t pour a garden-soil recipe into coir. Use the range on this page only as a range. Confirm with a local station and the product label.
Don’t do this first
- Don’t pour a garden-soil recipe into coir; don’t heap manure into substrate as if it were soil.
Rate range
Leachate EC / pH
Follow the crop stage
Measure every day, or on a rhythm.
Fertiliser
Follow the mix recipe, not a mu rate
A weak buffer: stay thin.
These are ranges. Confirm with your local extension station and the product label.
When you see Bags and soil beds in one house; recipes get copied the wrong way. Substrate has no soil buffer; EC is jumpy, test. Walk an S and mix — one hole is not the field.
Lesson video
2026-03-25 · Li Zeyu · For learning. Serious damage: local agronomist or a soil test.
For learning only. Fertiliser and pesticide decisions need a local agronomist and a soil test.
Not sure? Photograph the field to identify the problem