Around 2003 Wells Brothers introduced “Custom Mix”. A mix of triple screened compost, lava, and green sand. Our manufacturer has lost their source for lava sand. So, the lava sand has been replaced with expanded shale. Why expanded shale? It is something that every garden and bed can use. This is a temporary change until a more reliable source is found for lava sand. The price is still the same for a 40-pound bag. The “all the time” sale is also the same, when you buy 3 you get 1 free.