I grew the Top hat varieties from Gurney's and a couple from the local Nursery.
If I remember right,there are Blueberry varieties that didn't need 2 plants.
Acid loving plants usually need an acid soil because they LOVE/NEED lots of iron.
I grew mine in pots (20 gal. , NOT #20).
The varieties I grew were bread for their ability to withstand heat.
My plants never did much between the birds eating 75% of the berries and the pots limiting their size.
Way too much work for a handfull of berries.
Whenever I saw the plants look nasty,I added vinegar and iron (Liquinox)to the water.
It did seem that the 5-1-1 mix worked better (didn't add the Dolomite Lime).
Soils with lots of organics breaking down in them tend to be more acid at first.
I think that is why the bark based stuff worked better.
I actually think I used more like 3 - 2 - 1 -1 (Bark-peat-perlite-pomice.Pomice for weight,when the nursery plant got bigger,it was top heavy.Pot meeded more weight or wind blew it over.)
I'd advise,if you just want to grow blueberries in pots,do it without really expecting to get the tons of berries gurney's or whoever says.
If you grow them in the ground,grow full sized varieties that get big in the ground.
They took at least 2 seasons to put out a basket or 2 of berries in pots.
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