biostimulant · Guide
What is fulvic acid?
The smallest, most active fraction of the dark humus in healthy soil, and the part that actually gets inside the plant. What fulvic acid is, where...
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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anaerobic fermentation · Guide
Bokashi bran: what it is, and how to use it to compost
Bokashi bran is rice or wheat bran inoculated with EM-1 microbes — sprinkled over kitchen scraps in a sealed bucket, it pickles food waste in two...
alfalfa · Guide
Alfalfa meal: the organic fertiliser with a built-in growth hormone
Dried, ground alfalfa is one of the most underrated organic amendments in UK gardening. It also contains triacontanol, a naturally occurring plant growth regulator identified in...
Crop guides · Guide
Epsom Salt for Roses: Does It Actually Work?
Epsom salt for roses is one of the most repeated tips in British gardening, and one of the least supported by trial evidence. It helps on...
beginners guide · Guide
Organic vs chemical tomato fertiliser: which should you choose?
After fifteen years cooking professionally, I could taste how a tomato had been fed. The head-to-head on flavour, yield and soil, with the science behind it.
basalt · Guide
Volcanic rock dust: silicon and trace minerals | Dr Forest
Volcanic rock dust supplies silicon and over 60 trace minerals: the elements NPK fertilisers leave out. Here is the chef-and-soil-science case, plus the peer-reviewed evidence on...
boubly mine · Guide
Why does Wimbledon feed its lawns a Yorkshire-mined mineral?
Polyhalite Why does Wimbledon feed its lawns a Yorkshire-mined mineral? By Joe, Founder of Dr Forest · May 2026 In summer 2023, the Daily Telegraph ran...
how to fix yellow tomato leaves · Guide
Why Are My Tomato Leaves Turning Yellow? | Complete UK Guide
Yellow leaves on a tomato plant aren't one problem. They're a symptom of half a dozen different things, and the right fix depends on which one....
mycorrhizal fungi · Guide
What Are Mycorrhizal Fungi? A Guide for UK Gardeners
Mycorrhizal inoculants help most UK garden plants but do nothing for brassicas, beets or rhododendrons. The full list of which benefit and when to apply.
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.