These are some of my favourite gardening blogs & websites:

The English Garden

Grows on You- the community for garden lovers.

Gardening.co. uk - the total online gardening resource

GardenOrganic - Promoting composting in your community

George's Japanese Garden - stunning Japanese garden in Yorkshire, England. Very inspiring.

The Inadvertent Gardener

My Bit of the Planet - wildlife in a garden in Hampshire, England

John's Garden - north west England

PlantforLife - gardening advice and information.

Find Me Plants - search for plants with free database

Moosey's Country Garden - "An Eccentric Rambling New Zealand Country Garden"  A beautiful site chock-full of gorgeous photos to enjoy and for inspiration.

My Garden- a small private garden in Wales, UK

My Wildlife Friendly Garden

My Wildlife Sanctuary

National Gardening Association (USA)

Turning Earth- from a small Yorkshire garden (England)

English Country Garden

Wildlife Gardening with Jenny Steel

Gardens for Wildlife - Notes from a London Wildlife Garden

Great British Gardens - beautiful gardens to visit in Great Britain and places to stay nearby

Wild About Gardens

Our Beautiful English Wildlife Garden an impressive site with lots of info

Horticultural - Jane Perrone's organic allotment and garden blog

Allotment Blog - from The Guardian

My Tiny Plot- a small veg garden in Bath, England 

Gardening Advice & Tips:

Activities & information for young gardeners - RHS Campaign for School Gardening

Botany Basics

Compost This

Top 100 plants every garden should have - per Daily Telegraph gardening writer Val Bourne

Garden Ideas

The Gardener's Calendar - vegeatable garden planting guides

Gardener's Paradise - gardening tips

Gardening for bumblebees

The Gardening Register advice, articles, forums, etc.

GardenWorld - portal to links and info

Composting for Beginners

The Definitive One Page Guide to Composting

Glossary A - Z

No Ground? Use containers

How to Make Compost

How to make compost- compostguide

Introduction to Composting

Latin Converter - translate botanical names from Latin to common names (or vice versa)

My Garden - RHS's online community for gardeners

Organic UK- organic food growing tips, ideas

Permaculture: A Beginner's Guide

Plants & Trees

PlantCare

Right Plant, Right Place

Top Veg

Vegetable Gardening Club - tips and tricks

Vegetables in the Home Garden and the plants that help them to thrive

The Virtual Garden - garden design tool from the BBC

Weekend Gardener

Gardening Data

Gardens Guide - the premiere open garden directory in Britain

Great British Gardens - gardens to visit in Great Britain

Let's Go Gardening UK- portal to useful gardening links

Organizations:

National Council for the Conservation of Plants & Gardens

The National Gardens Scheme - gardens open for charity in England and Wales 

National Society of Allotments

Royal Botanic Gardens, Kew

The Royal Horticultural Society