certified organic nitrogen · Guide
High nitrogen fertiliser: what it does, and when to use it
A high nitrogen fertiliser is the right tool for one job: leafy, green growth. Here is what it does, when leafy crops and lawns actually need...
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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animal-free plant food · Guide
What is vegan fertiliser? A UK grower's guide
Most organic plant foods are built from fish, blood and bone. A vegan feed leaves the animal content out and supplies the same nutrients from plant...
application rate · Guide
How to apply fulvic acid: rates and method, with peer-reviewed dose data
How to apply fulvic acid as a foliar spray, soil drench and seed soak, with the peer-reviewed dose data behind every rate. Plus the hormesis rule...
Crop guides · Guide
Best fertiliser for tomatoes: an honest guide
Three choices decide your tomato crop before you pick up a bag: organic or mineral, dry or liquid, tomato-specific or all-purpose. A science-led, honest guide to...
foliar feeding · Guide
What is a soil wetting agent, and does your garden need one?
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...
Ascophyllum nodosum · Guide
Seaweed fertiliser, properly explained
Seaweed fertiliser is a biostimulant, not a feed — its value is in the bioactive fraction, not its tiny NPK. Here's what it does, the three...
chloride-free potash · Guide
Polyhalite vs sulphate of potash: which potash should you use?
Two of the cleanest potash options a UK gardener can buy. They look similar on the label, behave very differently in the soil, and answer different...
amino acids · Guide
Amino acid biostimulants for plants: what they do and which type to choose
Amino acids are pre-assembled nitrogen the plant can absorb and use without spending energy on synthesis. What the evidence supports, how enzymatic and chemical hydrolysates differ,...
biostimulant · Guide
Benefits of fulvic acid for plants
Eight specific benefits of fulvic acid for plants, each with peer-reviewed evidence. Plus what the field-trial data actually shows for lawns, flowers, fruit and vegetables, and...
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.