mineral soil improver · Guide
What is a soil conditioner? Soil improver explained
A soil conditioner and a soil improver are the same thing. The organic half and the mineral half, which suits your soil, and why neither is...
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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Soil science guides.
4-4-4 fertiliser · Guide
Organic slow-release fertiliser: up to 3 months
Two bags on the same shelf can both say slow release and mean quite different things by it. One meters a salt out through a shell....
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...
biostimulants · Guide
What is humic acid? The brown coal in the bag
Humic acid is the dark, alkali-soluble fraction of humus. What it is, where it comes from, what it does in soil and at the root, and...
foliar feeding · Guide
What is a wetting agent? The 60-second drop test
Pour water onto dry compost and a lot of it runs straight out the bottom, leaving the middle dry as a bone. A wetting agent lowers...
mycorrhizal fungi · Guide
What are mycorrhizal fungi? The plants they skip
Mycorrhizal fungi are tiny soil fungi that live in and around plant roots. They spread fine threads through the soil and bring back water and phosphorus,...
Soil science · Guide
How to make soil more acidic or raise pH: rates
To raise pH you add lime; to lower it you add elemental sulphur. Test first. Chalky soils fight acidifying and are better worked with than against.
17 essential nutrients · Guide
What is a fertiliser? What it does and how to read the bag
A fertiliser supplies one or more plant nutrients in a known amount. Seventeen essentials, how to read the NPK on the bag, and when an organic...
essential oil herbs · Guide
Zinc deficiency in plants: check the new leaves
Zinc deficiency shows on the newest leaves first: small, bunched, pale between the veins. It is rare in UK garden soils. Test before you treat; too...
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.