The size you choose really depends on how much watering you plan to do and how much space you are willing to allocate to a butt. Rain barrels that hold 100 to 150 litres are generally considered to considered small scale - they are fine if you have minimal needs in your garden and only wish to water patio plants and maybe greenhouse plant, fruit and veg.
If however, your watering needs are more extensive and you'll be tending to trees, shrubs, hanging baskets and flowerbeds, you're probably best choosing a container that hold 200 litres or more.
The Harcostar 350 litre Magnum Double Water Butt Kit is a great value package, costing around £80, and gives you a very impressive 700 litres of water storage. These barrels come with child-safe lids, which are essential if you have kids, and universal rain trap diverters to connect to your downpipes.
If you have the space and would rather have smaller butts in your garden, you can consider buying several mini butts and daisy-chaining them together with barrel-linking hose kits.
Water butts are traditionally round in shape but, as there popularity has continued to grow, manufacturers have started producing them in a variety of other shapes including octagonal, rectangular and square shapes.
Flat-sided barrels wall-mounted barrels are very space efficient and fit snugly against the wall of a house. Other popular styles in this price range include those which are designed to look like terracotta and are shaped like a beehive. Other choices include those which include a planter which is integrated into the top of a butt.
Sankey, Harkostar, Space Sava and Stewart are among the leading brand names featured in the £50 to £100 price range.