Onnu Biochar

Biochar Compost Mix for Seeds

£19.00 GBP

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A gentle blend of biochar and compost to give your seeds a perfect start in life. Easy to apply, you seeds will love the rich, fertile soil designed specifically for new, healthy growth.

Size 20L Bag 40L Bag Bulk Bag (1.7 m3)

Quantity

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✅ EBC-Certified Biochar ✅
📦 Free Shipping on all 20L & 40L bags 📦
🌿 Peat Free 🌿

Biochar (10%) and Compost (90%) blend

Our Biochar Compost Mix for Seeds is the perfect product for optimal seed germination and early plant development. This gentle blend of 10% biochar and 90% compost is thoughtfully curated to create an ideal environment for young seedlings, minimising the risk of nutrient burn and supporting healthy soil development over time.

The biochar component, produced through the pyrolysis of waste wood, enhances nutrient retention while creating an ideal habitat for beneficial microbes—perfect for nurturing young seedlings and plants. This sustainable, eco-friendly addition works harmoniously with premium compost, providing rich organic matter that gently decomposes to release essential nutrients for early root development. Together, these components create the perfect mix that enriches the soil with organic nutrients, supporting a balanced nutrient cycle. Nutrients are absorbed and gradually released to seedlings and plants, minimising nutrient leaching and fostering long-term soil health from the start.

Our biochar is EBC-certified, ensuring our products are safe, effective, and environmentally responsible. You can find out more about what EBC-certification means here.

Want a full rundown on biochar, how it is made, it's benefits and sustainability credentials? Click here to find out more.

Key Features

The biochar is mixed with premium compost made from coir, vermiculite and organic fertiliser.

Gentle Nutrient Release - Provides a slow and steady release of nutrients ideal for seedlings, reducing the risk of nutrient burn.

Enhanced Moisture Retention - The biochar's porous structure holds water efficiently, ensuring seeds and young plants have consistent moisture for healthy germination.

Optimal Aeration - Improves soil structure, allowing roots to access oxygen, which is essential for robust root development in early growth stages.

Microbial Habitat - Creates a favourable environment for beneficial soil microbes, supporting soil health and promoting nutrient availability for young plants.

Balanced pH -Helps moderate soil pH, making it suitable for a wide range of seeds and promoting balanced nutrient uptake.

Reduced Nutrient Leaching - Retains nutrients near the root zone, reducing nutrient loss and ensuring young plants have access to essential nutrients as they grow.

Sustainable and Eco-Friendly - Made from renewable materials, this blend is an environmentally conscious choice that supports soil health without the need for chemical fertilisers.

Application

Seed planting:

1. Prepare the Tray: Fill the tray with the Biochar Compost Mix for Seeds up to just below the rim, taking care not to compact it excessively. A gentle tap on a hard surface will settle the mix just right, creating an ideal base for your seeds.

2. Initial Watering: Water thoroughly and allow the tray to drain fully, ensuring the product is evenly moist but not saturated.

3. Seed Placement: Carefully place seeds on the surface of the mix, spacing them as needed. This ensures each seed has ample room to develop into a healthy seedling.

4. Cover with Mix: Add a layer of compost mix on top of the seeds, with a thickness matching the seed's size (e.g., cover a 1mm seed with 1mm of compost). This protective layer provides the seeds with the ideal conditions to sprout.

5. Water Gently: Use a fine rose watering can to moisten the tray lightly. Coir and biochar retain moisture well, so water sparingly. If needed, cover the tray with polythene or glass to maintain humidity. Always check moisture levels just below the surface before re-watering, even if the top layer appears dry.

6. Provide Indirect Light: Keep the tray in a location away from direct sunlight, as gentle, indirect light is perfect for nurturing germinating seeds without risking overheating or drying out.

Postage and Packaging

Shipping is free on all 20L & 40L bag purchases. Bulk bags are shipped on a pallet costing £49.99 each.

We expect to send out orders within 5 business days of receiving them, and they should arrive within 2-3 business days.

Please note: due to our evolving sustainable packaging strategy, product may not be shipped with the same bag design as shown.

Bulk enquiries

Looking for more than 5 bulk bags? For larger orders in bulk bags or delivered loose, and to benefit from our volume discounts, visit our commodities business, Onnu Bioflow, or email info@onnubioflow.com.

Onnu Bioflow

Want to trial biochar?

Running a trial? We can advise on how to set it up so you can measure the impact of the biochar. Contact us for more information!

Biochar

Factsheet

Our factsheet is a comprehensive guide for biochar and how it works. With summaries, glossaries, property tables, product descriptions and application rates, this fully-referenced factsheet can help you familiarise yourself with the world of biochar.

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