Amanda- have you got a local allotment society? Their products are much cheaper. I know it's fun nipping into the garden centres, but if you are like me, you'll also come out with a boot full of plants,new gardening gloves....bird feed...the odd birthday card... If you compare the prices of what you actually need ,you will be shocked. We are using vermiculite for the first time this year and it's about 5 times the price at the local garden centre.Becomes annoying eventually. Still like garden centres v much but I do feel cheated at times. Best to get to know what your local allotment society sells (will be v limited) and try and support them too. win win situation.