The site includes a plant identification feature through uploading an image via an app.
Primrose say the social network allows people to keep a record of their gardens and to discuss them too.
Primrose's Ian Charles said: "it's fun and inspiring. We feel the press doesn't show many 'real gardens' - we mainly see gardens owned by people like Monty Don who have all week to work in the garden. It makes a nice change to see what real people with limited time and money (and knowledge) can achieve in a garden, and to pick up tips from them on how to grow particular plants. It's nice to see a 'real plant in a real garden' for once, and so easy to use.
"When you wonder round your garden enjoying new sights, new flowers, it's takes about 30 seconds to pull out your phone, take a few snaps and upload to your garden on primrose.co.uk. If you don't have good data, the app will store the photo and upload when you next get wifi). These photos then becomes a time-stamped record for next year and following years.
"This could also be really useful if you want to sell your house in winter - just direct your prospective buyers to your pictorial record, and they'll see how fabulous the garden looks in spring and summer."