It's the cool weather making their ability to get things like iron a little more difficult.After the temps go up for a few weeks,the reddish color should change. Brady

Blueberries usually have colored new growth. The only thing that bothers me is all the dead twigs on the first one.

bboy yeah I don't know whats up with the bare branches. They prolly took a beating this winter being in pots and all but I'm hoping their new home will promote better growth.BTW are blueberries fast growers?

Mine get a few dead tips during the Winter also.I just prune them off.As long as the plants are putting out new growth each year,they are fine.
They should grow about a foot each year and a few new canes from the crown.Some varieties are more vigorous.
There is a guy in the Orchard forum,fruitnut,that's been testing with small amounts of Ammonium Sulfate and getting big results.There are pictures archived,from plants smaller than yours,growing to about five feet in a year.Right now there is a thread about calculating the amount of this fertilizer. Brady

Like other heath family plants blueberries are prone to water molds. Other problems are also possible - I would not wave off a consistent twig death as nothing if they were my plants.

That soil mix is NOT what I'd choose for container grown blueberries. Too much organic matter in the way of compost, worm castings and peat which will make the soil excessively moisture retentive and subject to lack of porosity via compaction.

Any long term container grown plant wants a very textural, durable potting soil - a high concentration of bark - and minimal amounts of organic matter that will breakdown and compress and eventually decompose. Blueberries want a pretty acidic soil as well. I'd look for Gardner & Bloome or Master Nursery's acid planting mix (same product sold under two different labels). This is a heavy duty, very barky mix specially formulated for acid loving plants. It holds up very well over time.

Yes, if the mix gets old and breaks down before you replace it heath family plants in particular will deteriorate and die. The dead twigs could indicate inadequate aeration, a situation which encourages water molds (as does letting sun beat on black pots during warm weather).

Hot + wet = rot.

Even if the mix is not soggy now plants infected at time of purchase will often continue to be attacked.

I use about a 60/20/20 mix of conifer bark mulch/peat moss/perlite in containers and skip the perlite for in ground and they grow great. Brady

The colored new growth leaves look just fine. Normal, as bboy says. .......so far. I'd put them in larger pots though. It's easier to care for them. They probably outgrew their previous containers and dried out a bit, causing a little bit of die back.
As far as the mix for the potting soil, don't blueberries grow in boggy soil? I've only grown a few, so I'm no expert, that's for sure.
Any reason why they aren't in the ground?
Mike

Double post.

This post was edited by mikebotann on Wed, Apr 30, 14 at 7:56

Thanks all for the responses. Usually if I put plants in pots I make 5-1-1 mix. But I was lazy this time around. I'll snip off the dead growth and keep an eye out for any other issues. If the dead end persist I'll toss the whole plant and start over.

Okay Mike,how do I make boggy soil? Brady

Like all heaths, blueberries are prone to root rot - the tradition of planting them in former peat bogs must have been possible because the sphaghnum was suppressing the water molds, the soil (and water) was too cold or some other factor was allowing it to work.

In other words, there are different kinds of damp ground. Thuja occidentalis grows in swamps in the wild but if you try and plant it in a mud hole in a garden it is liable to die. In fact, the highly prevalent T. o. 'Smaragd' is quite drainage sensitive.

That brings up another thing bboy.Why did people plant them in peat bogs?I'm thinking it was after the discovery by Dr.Coville that Blueberry plants need an acidic environment to thrive.Because from what I've read,people tried in vain to grow them in 'regular' soil and peat is of course is acidic.
Right now,a home gardener in Colorado is growing them,from advice from either an extension agent or University staff,by digging a trench and putting in bales of unopened peat,poking holes through the plastic for drainage and to plant and then covered with soil.This is done because the soil is highly alkaline and the plants are doing well,last I heard.
For me,growing in containers gets much better growth and there is no contest compared to in ground.I had to rescue a few and pot them and they take off.I think it's because I can provide a better pH environment,among other things for them.
Here's a photo and little writeup,like what the lady is doing in Colorado.I thought it was kind of crazy when first seeing it. Brady

Here is a link that might be useful: Blueberry Bale