calcium · Guide
Does liquid gypsum work on clay soil? Test first
Yes, on most clay that waterlogs. Dissolved gypsum keeps the surface from sealing, and that does not depend on sodium. The dispersion test shows how strongly...
Allotment gifts for Christmas
Feed sets and gift cards growers actually use. Shop allotment gifts
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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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...
calcium and sulphur · Guide
What is liquid gypsum?
Water holds about two and a half grams of gypsum in a litre, and then it stops. That single number explains why liquid gypsum is a...
alfalfa for lawns · Guide
Alfalfa for lawns: a slow feed that won't scorch
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
Organic dry amendments: the 3 most gardens need
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? Does more P mean more flowers?
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? 690 trials say it helps
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
Humic acid benefits 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: why more isn't better
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...
The garden journal
Feeding schedules, soil science & 10% off your first order.
One letter a month on what to feed, when to feed it, and why it works. Written by Joe, for growers who want to understand their soil.