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Crocus frasstastic bio-mulch

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Good mulch is one of the best investments you can make in the garden, a protective, breathable soil blanket that helps retain moisture, suppresses weeds and insulates roots from extremes of weather.

But we fancied making a mulch that works harder for the garden, not just covering the ground, but actively nourishing and supporting the living ecosystem beneath it. Our new frass-tastic bio-mulch is brimming with soil-feeding goodness (and other magic) to help you build a healthy garden from the ground up.

What’s the magic in our mulch?
  • Insect frass is the star ingredient. Produced by black soldier fly, who are reared on spent brewery grains, this organic natural fertiliser supplies nitrogen (3%), phosphorus (2%) and potassium (1%), along with healthy trace amounts of iron, manganese, zinc, copper and boron, plus smaller amounts of calcium and magnesium to support balanced plant growth.
  • Chitin (a natural material that makes up the insects’ shed exoskeletons). This not only feeds the beneficial fungi and microbes in the soil, it’s proven to activate plants’ immune responses, which gives a natural boost to their overall health and stress resistance.
  • Willow fibre encourages healthy aerobic decomposition, which improves soil structure naturally. Our willow comes from a mix of five strong cultivars grown and sustainably harvested across 17 sites in England. The chips are screened to around 30mm, so they knit together neatly in beds and borders to give excellent coverage with less material.

The science bit

As the mulch slowly breaks down, fungi and soil organisms get to work converting the willow and frass into plant-available nutrients and organic compounds. These act as a buffet for the soil food web, helping bacteria, fungi, worms, and other microorganisms flourish.

The result is healthier, more fertile soil with better structure, improved microbial life, and ultimately happier plants.

How to use:

Apply a 7-10cm layer to moist soil, keeping mulch clear of stems and woody crowns. Water after application and top up as needed. Suitable for beds, borders, vegetable plots and around trees and shrubs.

Store in a cool, dry place.

Key features:

  • Feeds soil and soil life as it breaks down
  • Stimulates plants' natural immune response for better stress tolerance
  • Reduces weeds, conserves moisture and improves soil structure

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