Crop guides · Guide
Best fertiliser for tomatoes: twice the potash
For most home growers, the best fertiliser for tomatoes is a tomato feed with more potash (the K on the label) than nitrogen (N), started when...
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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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...
Ascophyllum nodosum · Guide
Is seaweed a fertiliser? A biostimulant, not a feed
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 to buy?
Clear pick for UK gardens: polyhalite for season-long K, Ca, Mg and S; sulphate of potash when fruit and flower need a fast hit. How to...
amino acids · Guide
Amino acids for plants: how I use them
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
Fulvic acid benefits for plants: 8 trial results
Iron locked on chalk, thin roots in a tired grow bag, fruit marking even with calcium in the bag. What peer-reviewed fulvic trials actually show, and...
biostimulant · Guide
What is fulvic acid? A grower's one-line answer
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
How to use bokashi bran: the mistake I see most
Bokashi bran is wheat bran inoculated with EM-1 microbes. Sprinkle one to two tablespoons of Bokashi bran per kilo of food waste in a sealed bucket,...
alfalfa meal · Guide
What is alfalfa meal? Is it a good fertiliser?
Alfalfa meal is dried, milled lucerne sold as a slow-release organic fertiliser. What is actually in it, how slowly the nitrogen arrives in cold British soil,...
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.