Imo, now may actually be a better time to prune blueberries. You can notice dead wood and older canes that should be cut out totally. Your bushes will benefit from the pruning, even if flowers are open.

I can only speak to Southern Highbush Blueberries (SHB) grown in containers. Prune after they finish fruiting. Prune to provide balance with the amount of roots in the pot. Remove low wispy branches. Make thinning cuts on old unproductive woody branches to promote the growth of newer thicker shoots. These new thicker shoots will be your future fruit bearing wood.

Thanks all. I was just rereading all my pruning info, which I think I mentioned has different schools of thought from a few different sources. But in general the key things all sources seem to mention are: removing crossed branches....keeping the center of plant 'open' to allow light and air...and removing any branches that are low or touching the ground. On this last point, I am squeamish about cutting off one branch that I see that is almost touching the ground, and since it has healthy buds on it. I hate to 'waste' that branch. ;-) Should I really remove it?

One of my pruning directions is so detailed and confusing but...I know sometimes people can go a bit overboard and be overly-specific and that in general, 'nature' takes care of itself. So I'm trying not to get too stressed out about this whole pruning 'regimen'. But like for example, another site talks about blueberry shrubs and 'canes' that are 'five years old' and that a shrub should have 'X' number of five-year old canes and any beyond that should be pruned out etc. But how is anyone to know how 'old' each cane is??

Do I not need to worry so much, and just focus on the key points of removing crossing branches, keeping center of plant open, and removing any low branches touching the ground, and leave it at that?

I know that BB's like acidic soil so I want to add some ammonium sulfate now to my two potted BBs. (Previous testing of the soil showed it was 'neutral'.) I've no idea what the general proportions are for ammonium sulfate to water....I'm assuming maybe just a tablespoon or so of ammonium sulfate per plant, mixed with water?

If your pH tested neutral then you should also add elemental sulfur. You could add more ammonium sulfate then a tablespoon full per plant but surely not enough to change the pH enough. I would also add abundant pine based mulch around each plant.

I remove most lower,sprawling branches because from my experience they end up on the ground when it's time to pick and I don't like lifting branches off the ground to pick or tying them up to keep them up. Picking is enjoyable for me but low branches mean more bending and less enjoyment. I actually cut a few low branches off every week last year, inserted them into drilled logs and encouraged children to pick free blueberries at our farmers' markets. I thought that was the best use for those branches.

Thanks. I did add about an 1" thick of evergreen needles to both plants around Christmas time (asked the local tree seller for a bag of what they sweeped up at night ;-). I also have some bloodmeal but it's my understanding that it does the same thing as ammonium sulfate and that I should only use one or the other?...that bloodmeal is considered organic while the other is not.

I also have some 'homemade' compost but read that that's not good for blueberries..?. maybe that it doesn't have the desired effect on the pH level?..

Bloodmeal = ~12-0-0

Ammonium sulfate = 21-0-0

Ammonium sulfate is like plant steroids. Bloodmeal is slow while the sulfate is instant. Understand where bloodmeal comes from and at best I would call it non-synthetic, not organic but that is only my opinion.

Stick to acidifying mulch only. Pine needs, pine bark, peat, used coffee grounds, etc. Cottonseed meal will work to acidify the soil and as a slow release fertilizer; much cheaper than bloodmeal too.

I'd like to find ammonium sulphate locally but have not seen it. I've been using holly tone soil acidifier but I think it uses elemental sulfur.

Many lawn fertilizers are AS and can be used.

Drew, that is a great video. I have great respect for the Fall Creek Nursery since I purchased most of my plants from them. The only point I questioned was the length of the stub left after pruning out an entire cane. Dean Polk, Rutgers, had given a pruning seminar and his point was to prune as close to the root crown as possible. There might be a trade-off since there have been times where I was not able to remove a cane without scraping adjacent canes.

I agree as low as possible without damaging the plant. I like that video and agree with most of it. Over bearing does lead to unproductive canes at least on my plants. Some key points heading to new growth, a very good way to keep canes productive.

Removing canes stimulates new ones, yes it does.

The more experienced I become it seems the harder I prune. It's tough to prune properly. Seeing results really helps. I'm still learning myself.

http://www.amazon.com/Hi-yield-32177-Ammonium-Sulfate-Granules/dp/B000OV85BQ

You should be able to find smaller bags like that Hi-Yield brand above. Try places that sell to rural/farm. 50lb bags are also very cheap there.

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That pruning video is for a u-pick farm. That seems overly aggressive for home usage especially when he started to stomp-prune branches off.

He did show how that kind of pruning can lead to excessive damage, yes use pruners! But the heavy pruning he did will produce bigger, and sweeter berries.

He did say remove all but 4-8 fruiting laterals on each cane, well leave 8 then! That is plenty per cane. Unless your goal is pure numbers and not taste or size. Plus removing them stimulates growth for next year. I have had my older plants become unproductive from under pruning. Once that happens, you get it. Now some cultivars may not respond or need that much pruning. Cultivars do all grow differently. Leaving 10-12 laterals per cane maybe OK depending on cultivar.

I agree don't go ripping branches off, unless you have that many too. I do know people with that many!

The main purpose of that video for me is to get an understanding of why you prune, and what it does. Feel free to experiment. Leave more laterals on one cane and not another and compare size and taste for yourself.

Plants have limited resources. The leaves produce the sugars, and so the more berries, the less sugar each berry has. Simple physics.

I grow peaches too and probably remove 70-80% of the fruit. This produces outstanding peaches, plus how many do you really need? I have 4 trees, I get plenty and they ripen at different times throughout the season.

@Lynn Nevins, I'm wondering if it might be helpful to break things down a bit more. If so, I would consider removing crossed, diseased, dead branches and opening up for light & air flow to be general pruning concepts, and not specific to BB. So too for branches that are way out of balance, Those general points definitely apply.

At this point we have no idea if your BB are in pots, if they are SHB, or where you are located. This level of detail is important.

Also if your BB are new, say 1 to 2 years old, you can let them go a bit until you figure out your plan of attack. If you see branches that are making the plant sit way off kilter, you can prune just enough to maintain some balance for now.

I'm not a fan of using ammonium sulphate or high doses of any water soluble nitrogen for any plants (in ground or in pots). That's based on my own years of experience having tried that approach on everything from lawns, shrubs, annuals and BB. If that's the path you choose, that's OK, but know that it's not the only path.

There are a lot of variables to consider when pruning and some things are just adjustments to what one person may have been doing. The variety alone makes a huge difference as Drew already mentioned. I have about 75 Reka bushes and they produce far too many canes for their own good. Without severe pruning I wouldn't care to pick berries, abundant, yet small. Next to them I have a row of Chandler that I could just not find reason to prune at all until I took note that no new canes were growing. A few years ago a small fruit specialist at our nearby university had written an article specifically mentioning that Chandler needs to be pruned harder just to force it to produce new canes. I now will cut out a few canes on each Chandler bush for no good reason except to pay-it-forward.