The trade and DIY store Wickes have a reasonable range of outdoor garden storage products, available in over 240 of their stores Nationwide as well as from their online store at https://www.wickes.co.uk.
Their product range for outdoor storage seems to be limited to small to medium sized units, suitable for bikes, lawnmowers and garden tools. They stock both plastic and wooden storage units from a variety of brands including Rowlinson, Keter as well as their own Wickes brand.
If you would like to see more of the Wickes garden storage range, visit this link: https://www.wickes.co.uk/Products/Gardens/Garden-Buildings/Garden-Storage/c/1000728?q=%3AtopSellers&page=0&perPage=30
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