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Gardening Journal

This excellent Moleskine notebook with 5 themed sections

Keep all your garden notes in one organised place.
This excellent Moleskine notebook has 5 themed sections:

Plants

Pots, Tools

Design

Visits

Garden Log

And 5 further tabbed sections that you can personalise.

Lined and squared paper to make notes and sketches.

Bags of useful reference information :

Glossary of leaves

World Hardiness Zones

Plus a back pocket to store rip sheets, seed packets and other stuff.