FGD gypsum · Guide
Natural vs synthetic gypsum: does the source matter?
Two very different industries make calcium sulphate. One digs it out of rock, the other scrubs it out of a chimney. What the difference is actually...
The Dr Forest blog · Est. Stockport · England · 2020
Soil science & growing guides, properly explained.
Evidence-led guides to organic fertiliser, feeding and soil science for UK growers. Deficiencies, ingredients, biostimulants and crop-by-crop feeding, with every claim checked against the original paper.
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calcium and sulphur · Guide
Why liquid gypsum is a suspension, not a solution
Gypsum barely dissolves. About two and a half grams in a litre of water, and then it stops. That single number explains why liquid gypsum is...
alfalfa for lawns · Guide
Alfalfa for lawns: a real organic feed, held back by its own strength
Alfalfa is a genuine slow-release organic lawn feed, but at 2.5% nitrogen it is mild for the hungriest thing you grow. What it does for turf,...
bokashi · Guide
What are organic dry amendments?
What organic dry amendments are, the main categories, and which ones your soil actually needs. A plain guide to feeding the soil, not the plant.
available vs total NPK · Guide
What is a bloom fertiliser?
A bloom fertiliser is a lower-nitrogen, higher potassium and phosphorus feed for the flowering and fruiting stage. Why the big middle number is not what the...
all purpose fertiliser · Guide
What is living soil?
Living soil is soil with a working population of bacteria, fungi and worms doing the job of turning organic inputs into something a root can use....
biostimulants · Guide
Benefits of humic acid for plants
Eight peer-reviewed benefits of humic acid for plants, each with the trial behind it. What the field data shows by crop, and where the evidence is...
biostimulants · Guide
How to apply humic acid
How much humic acid to use and how to apply it: soil incorporation, root drench and foliar rates, timing through the season, and the common mistakes...
Ascophyllum nodosum · Guide
Benefits of seaweed fertiliser for plants
Seaweed's benefits come from its bioactive fraction, not its NPK: faster rooting, heat and drought tolerance, chlorophyll retention and yield. What the better trials show, including...
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