Planting Fruit Bushes ?

[Estcourt]

Please can someone help?

have set posts in concrete for me to grow..Raspberry,Blackberry,Gooseberry and a Tayberry...as follows|......|.......|.......|......| Space between posts are 6-8 feet each one!
My question is .....How many plants of each should i plant between each?
I thought that 1 plant of each is o.k. ??

will also be making ties between each post fo support!

also would it make any difference which ones are next to each other at all!

[Estcourt]

[Merry Tiller]

Raspberry - 1 foot apart
Blackberry & Tayberry - 8 foot apart
Gooseberry - depends how you train them, mine are fan trained and planted 4 foot apart but if you grow them as single cotdons they should be about1 foot to 18 inches