You can get by with one pollinator for several trees . Does not have to be 1 to 1 . Crabapples also work if you already have flowering crab . There are a few that self pollinate like golden delicious . 2 in one trees are also available . Lots of optionsThanks! So if the ones I planted are, say, gala. I should plant granny smith next to each gala apple tree so they cross pollinate?