alfalfa meal · Guide
What is alfalfa meal, and 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 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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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 feed: 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
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
Polyhalite: why Wimbledon feeds its lawns a Yorkshire-mined mineral
Contents First, what polyhalite actually is Four nutrients in one crystal How polyhalite ended up on the centre court What polyhalite actually offers Polyhalite or muriate...
Epsom salt for tomatoes · Guide
Why are my tomato leaves turning yellow?
Tomato leaves turning yellow usually name a cause once you know where the colour starts. Finger in the compost, then read the leaf: bottom, top, or...
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.
Soil science · Guide
How to make soil more acidic, or raise the pH
In organic gardens you'll often hear that pH doesn't matter because the soil buffers it. Only partly true. pH drifts even in well-tended organic systems, slowing...
17 essential nutrients · Guide
What is a fertiliser?
A fertiliser is any material you add to soil or to a plant to supply one or more of the nutrients it needs to grow. Seventeen...
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.