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Plagron Mega Worm Organic Worm Castings, 1L, 5L & 25L
Plagron Mega Worm is pure, organic worm castings: 100% castings from Dendrobaena worms, rich in humus and soil life, for bringing tired compost and garden beds back to life, in 1, 5 or 25 litre sizes.
Think of the dark, crumbly, sweet-smelling soil you find under a log in the woods. Mix a few handfuls into your tomato pots or sprinkle it along the herb bed, and you’re giving plants that same living richness.
Worm castings that bring your soil to life
Mega Worm isn’t a quick fertiliser. It contains very little that plants absorb directly; instead it’s full of soil life, enzymes, mycorrhiza and trichoderma that slowly turn organic matter in your compost into food the roots can use. The result is a steady, gentle supply rather than a sudden rush.
It’s CU-certified organic and made by worms doing what they do best, so it suits a natural, chemical-free way of growing. Children love the idea that worms made it, and it’s a lovely, hands-on way to talk about how healthy soil works.
What worm castings help with
- Refreshing old compost in pots and window boxes
- Enriching compost for tomatoes, salads and herbs
- Top dressing houseplants
- Improving vegetable beds and raised beds
- Making your own rich potting mix with coir or compost
Living soil, made by worms
- 100% worm castings. Pure castings from Dendrobaena veneta worms.
- CU-certified organic. Suitable for organic, chemical-free growing.
- Full of soil life. Contains mycorrhiza and trichoderma that support strong roots.
- Slow and steady. Rich in humus and trace elements, released gradually by soil life.
- Three sizes. A 1 litre bag for houseplants up to 25 litres for the veg patch.
Worm castings: your questions answered
How do you use worm castings in potted plants?
Mix them into your potting compost at about 10–20% by volume, which is Plagron’s guide of 100–200 litres per 1,000 litres of soil. For established pots, sprinkle a thin layer on top and water in.
How much worm castings for a garden bed?
Plagron recommends 1 litre of Mega Worm per 3–5 square metres outdoors, worked lightly into the surface.
Are worm castings a fertiliser?
Not in the usual sense. They contain little directly absorbable feed, but the soil life inside converts organic matter into nutrients the plant can take up.
Why are there no worms in worm castings?
The worms have already done their job. The castings are what they leave behind, so you get all the benefit without live worms.
The details
| Product | Organic worm castings, soil improver |
|---|---|
| Composition | 100% worm castings from Dendrobaena veneta |
| Organic | CU-certified organic |
| Contains | Humus, trace elements, enzymes, mycorrhiza and trichoderma |
| pH | 6.5–7.5 (1:1.5) |
| EC | 1.0–1.7 mS/cm (1:1.5) |
| Dose in pots | 10–20% of the potting mix |
| Dose outdoors | 1 litre per 3–5 m² |
| Sizes | 1, 5 or 25 litres (see table) |
| Brand | Plagron |
Sizes and measurements
| Size | Volume | Treats roughly |
|---|---|---|
| 1 Litre | 1 L | 5–10 litres of potting mix, or 3–5 m² of bed |
| 5 Litre | 5 L | 25–50 litres of potting mix, or 15–25 m² of bed |
| 25 Litre | 25 L | 125–250 litres of potting mix, or 75–125 m² of bed |
In the box
1 × Plagron Mega Worm worm castings in your chosen size.
Rich, living soil, made by worms and ready for your best season yet.