problems with blueberry and blackberry plants

Hello everyone, I'm new to this forum and I'm in need of some help. I got a blueberry bush and a blackberry that I bought not long ago but they seem to be having some problems the new leaves on the blueberry are yellow and the old ones were turning brown, I though it was a fungus and caught most leaves and canes that had berries but still keeps going. I live in Lima, Peru and its summer here, a really hot summer with intense radiation and 31º plus celsius that's like 90ºF. I used some acidic fertilizer just in case but don't know if that made it worse. What should i do?

About the blackberry some leaves are turning a bit purple on the tip but not much, that's about it.

Hi Roberto, welcome to permies!

I think your blackberry looks fine. The blueberry is experiencing chlorosis, which being blueberry I suspect is from an iron deficiency. Blueberries need iron, moreso than most other edibles. Blueberries like a soil with an acidic pH, 5.5 is a safe number to target. Iron becomes less available as a soils pH gets less acidic, or goes up closer to neutral. Adding amendments to acidify a soil takes time for it to work, sometimes a year or more. What kind of soil is it planted in?

All my blackberry leaves turn purple in the fall. Since its almost spring on my side of the world, is it almost fall there?

And to reiterate, i cant grow blueberries in the same soil as blueberries. For me the only way blueberries grow is in 100% peatmoss and rainwater. My well water is very alkaline and kills it.

Hey Roberto - I am growing blueberries in Curitiba, Brazil (1000m elevation, a bit less hot than Lima but this summer has been a hot one) and I have 3 plants. Two drop their leaves regularly, like twice a year, and get totally naked, but then put on new leaves. I have no idea what their problem is. The third one keeps its leaves and is putting out suckers. They all get the same care. And they all tend to have yellow leaves, except for when it gets cold (we get down below zero a few times), then they get red. I feel like the blueberries are a mystery to me, so I am following this thread!
I will look at iron, but our soil is mostly clay and acidic to start with.

James Freyr wrote:Hi Roberto, welcome to permies!

I think your blackberry looks fine. The blueberry is experiencing chlorosis, which being blueberry I suspect is from an iron deficiency. Blueberries need iron, moreso than most other edibles. Blueberries like a soil with an acidic pH, 5.5 is a safe number to target. Iron becomes less available as a soils pH gets less acidic, or goes up closer to neutral. Adding amendments to acidify a soil takes time for it to work, sometimes a year or more. What kind of soil is it planted in?

The container is mostly peat moss with compost and worm castings and mulched with pine needles.  I think the water though is very alkaline and I dont know if I made it worse with the fertilizer. I'm getting some test strips soon to test the ph. Can I use vinegar to acidify my water? It doesnt rain much here. How can I lower the ph?

About the change of seasons for blackberry, yes its almost fall or at least supposed to be but temps are just getting hotter this year no sign on it cooling down.