application rate · Guide
How to apply fulvic acid: rates and method
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...
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.
Search the guides
Older guides.
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
What is seaweed fertiliser?
Seaweed fertiliser is a biostimulant, not a feed: its value is the bioactive fraction, not its tiny NPK. What it is, where it comes from, the...
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: what actually works
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...
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...
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...
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.