John Innes No. 3 Compost 35L bag - By Jamieson Brothers

John Innes No. 3 Compost 35L bag - By Jamieson Brothers

£17.49

JAM22

Pack Size: 35L

35L

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John Innes No. 3 Compost 35L bag - By Jamieson Brothers

35L

£17.49

Product Description

John Innes No. 3 Compost 35L bag - By Jamieson Brothers

John Innes No. 3 is a nutrient-dense compost, perfect for mature plants, shrubs, trees, and climbers, including fruit trees, bushes, vines, and vigorous plants like tomatoes and chrysanthemums.
Formulated with loam, water sand, and high levels of essential fertilisers (NPK), along with being aerated to provide minimal resistance to roots while promoting vast root development, healthy growth, and ensuring excellent drainage. It delivers the nutrients required for strong growth and vibrant health. This compost ensures excellent drainage while retaining moisture, preventing root rot, and is ideal for long-term potting of established plants that need sustained feeding and strong root support. As the richest blend in the John Innes range, No. 3 provides triple the nutrients of John Innes No. 1, making it ideal for mature plants that will remain in their pots for extended periods.
We offer suitable blends of specific compost which contain John Innes no.3 such as Fruit, Tree and Shrub Compost
John Innes compost is a well-known and trusted range of compost blends developed in the UK. It was created in the 1930s by the John Innes Horticultural Institute and is known for its balanced, nutrient-rich formulas that support healthy plant growth. The compost is named after John Innes, a philanthropist who funded the institute.
There are different types of John Innes compost, each designed for different stages of plant growth:
John Innes No. 1
Our Seed Planting Compost and Bulb Planting Compost
Designed for young plants, this mix has a slightly higher nutrient content to support initial growth after seeds have germinated.
John Innes No. 2
A balanced compost suitable for repotting established plants into larger pots, with a nutrient level ideal for sustained growth.
John Innes No. 3:
This compost is formulated for mature plants and trees that require more nutrients for continued development.
John Innes compost is highly regarded for its good structure, water retention, and balanced nutrients, making it a reliable choice for both amateur and professional gardeners.

Features

Feed 6 Months
Filters Moisture
Retains Moisture
PH 5.5-6.0
+ John Innes

John Innes No. 3

Professional, specially formulated John Innes No. 3 compost designed for mature plants, shrubs, trees and long-term containers. The John Innes No. 3 formulation provides added body for established plants. Ideal for potting established plants that need lasting stability, this substantial, loam-based blend helps provide weight and dependable root anchoring, supporting long-term establishment in larger pots and containers.

Perfect for:
Mature Shrubs
Fruit Trees
Ornamental Trees
Established Roses
Bay Trees
Olive Trees
Acers
Large Houseplants
Permanent Containers
Patio Shrubs
Long-Term Planters

FAQs

Please read our FAQs page to find out more.

Does your compost contain pests or fungus?

Fungus gnats are a common frustration with many mass-market composts, but we take plant health seriously. Our compost is professionally screened and stored in a clean environment to ensure it is free from infestations. By choosing our specialised mix, you are making the correct decision to keep your home pest-free while providing your plants with a clean, healthy start.

How will your compost make my crops & plants thrive?

When plants reach their full potential, they need a substrate that can keep up with their demands. Jamieson Brothers John Innes No. 3 is our most robust, loam-based potting mix, specifically engineered for established shrubs, fruit trees, and permanent container displays. This 35L bag delivers a high-nutrient formulation that provides a sustained release of energy, ensuring your garden's stars don't fade after one season. The added mineral weight provides superior stability for tall plants, preventing pots from tipping, while the traditional recipe ensures perfect moisture management and drainage for long-term health.

Does your compost contain large bits of bark (garden waste) or random seeds?

A common complaint with cheaper alternatives is finding "green waste" or unwanted seeds in the bag. Our John Innes No.3 Compost is a refined, high-quality medium that is strictly monitored for purity.

You can be confident that you are receiving a consistent, professional-grade product that contains only the nutrients and structure your houseplants need, with no unwanted surprises or contaminants.

What's the structure & consistency of your compost?

Inferior composts can often arrive bone dry or as a fine dust that is difficult to water. Because our mix contains John Innes, it has a much better physical "body" and weight. This helps it retain the correct amount of moisture without becoming waterlogged or dusty. It is easy to handle and provides the perfect air-to-water balance that is essential for the delicate roots of indoor varieties.

Why is this specialised mix a better investment than a cheaper compost?

Buying a “bargain” compost often leads to the hidden costs of purchasing extra feed, adding weight and structure or repotting mature plants sooner than expected. Our John Innes No. 3 Compost is an all-in-one professional solution. Its substantial, loam-based formulation provides dependable moisture stability, anchorage and root support for established plants.

It is the most reliable choice for mature plants, shrubs, trees and long-term container displays.