Cold weather causes it, just give it time.

southern California here. It has been warm since February.

Ive seen too low of a ph cause redish color leaf tips. Some are even on the pink and yellow side. I dropped the ph in alot of my potted plants last year and different responses depending on cultivar. One for sure sign on all plants was stunnted growth with really small leafs and red to pink to yellow and pink color. Do you have a way to check soil pH?

Attached is a photo

Another

Yup, you got a problem.

Have you checked the pH? Looks like it could be on the low side, just a guess???

Did you add sulfer to that potting mix?

If so, how much and how big of a pot?

What variety is that?

You said red leaves....you didn't mention the severe chlorosis lol:) Your PH is way off though I'm not sure if it is too high or too low. My guess is too low.

I would recommend a plant leaf analysis. They usually also do a soil analysis with that. Check with your extension office or ag office. In Wisconsin, I think it costs about $30. It provides N,P,K,Ca,Mg,S,Zn,B,Mn,Fe,Cu and sometimes Al and Na as well as Ph. They will give you current levels and desired range. And since this is what is in the plant, it is really what counts and eliminates the guesswork.

One way to check soil pH is to water the plant with distilled water, and collect some of the excess that runs out of the bottom of the pot. A small sample, about 5 ml, is all you need for a pH test. Add a drop or two of bromocresol green indicator solution. It will turn blue if the pH is 5.4, or higher, and it will turn yellow if the pH is 3.8, or lower. If the solution turns green, the pH is around 4.6, and that would be optimum for blueberry shrubs. Low magnesium and low iron can cause chlorosis, so you might consider using a water soluble fertilizer that has these two nutrients included. Not too much, though. Bromocresol green can be hard to find, but they have it at HMS Beagle, 4 dollars a bottle, enough for about 100 tests.

UCCE hasn't done soil tests for years.

What did you use to fill the containers?
If potting soil, did you add sulfur? If so, it's easy to add waaaaay too much. Better to use an "acid potting mix" suited to azaleas & camellias, as is.

If in the ground, your pH is too high.

It would be worth contacting your county's Extension Service office. Locate it with this interactive map:
http://www.csrees.usda.gov/Extension/

Here is a link that might be useful: locate your county's Extension SErvice office

They are in pots. I used potting mix and added ag Sulfer. First tablespoon did not do enough, so I added two more. Maybe now it's too high. I will check the soil PH.

Congratulations! You have officially cooked your first blueberry plant;) Get your water hose and crack it open to a slow flow and let run for an hour or two and then check the pH of the water coming out of the pot. Keep it going till you reach at least pH 5. Chances are you will have to do it again in another month or so as there is probably more sulfer that has yet to break down. Better yet you should pull the plant and wash off as much of the soil as you can from the root ball and replant in fresh soil. I only use 1 tsp in a 15 gallon pot mixed up in the potting soil before planting. I use rain water though so my pH doesn't drift once it stabilizes. If your using tap or well water you will have to check pH at least once a year maybe more. Good luck!

I only use 1 tsp in a 15 gallon pot mixed up in the potting soil before planting.

I'm always curious about blueberry potting mixes -- what's in yours, blueboy?

In the past i've potted blueberries in 100% peat moss and just use a recommended acid loving fertilizer...never any issues. I also would use rain water as much as possible.

I think my soil PH might be too high actually...
Not sure if we are talking apples to apples, I used this stuff:

http://www.homedepot.com/p/Espoma-6-lb-Soil-Acidifier-100508616/203192757#product_description

It is organic elemental sulfur. not sure what ag sulfur is, aluminum sulfate?

My soil barely droped from 7.0 with one tablespoon. I don't think it does a very good job of lowering PH.

I did however add two tablespoons of organic acid fertilizer. Not sure if maybe that was too much...

Soil bacteria transform elemental sulfur to sulfuric acid, which in turn lowers pH. Therefore, while it's a very effective way to lower pH, its effects aren't immediate. If you used a regular potting mix (as opposed to one with acidic components), added sulfur, and planted immediately/recently (so that sulfur hasn't had a chance to break down), your issue probably is high pH (you'll need to confirm that with a pH test, of course). While acid forming fertilizers can help lower pH, they too take time to act and won't have nearly the same impact as sulfur.

So, just to be clear, you added only one tablespoon of elemental sulfur (Espoma Soil Acidifier)? How large is your pot/container? Finally, what's in the organic acid fertilizer that you used?

This post was edited by shazaam on Thu, Apr 25, 13 at 16:59

I used one tablespoon on the epsoma elemetal sulfer, checked PH (was too high), then added two more tablespoons.

In addition, I added a total of two tablespoons of the following:

http://www.ebstone.org/11_azalea.php

not sure what is in it without looking at the box.

I will buy another test kit and test the soil PH today. My guess is I will be high. Maybe the soil sulfer and fert. have jacked up the dissolved salts level, and is preventing nutrient uptake. It is after-all in a 15 gal pot.

" My soil barely droped from 7.0 with one tablespoon. I don't think it does a very good job of lowering PH. "

It works well actually, but may take from one month to three months to work. The bacteria have to break it down.
Yes it could not be working yet, or is working too good. Depends on the pot size and how long ago you used the product, which is an excellent product.
With blueberries you need to test the PH, it's the only way to know what is going on, high or low, the plant cannot take up nutrients, so yes, the plant is under extreme stress at the moment. No doubt it will take a long time to recover once you get it right.

Sulfur must be acted upon by soil organisms which convert it into a form plants can use.
That process proceeds slowly, over a period of months, in the ground, but extremely slowly in containers.

I doubt that leaching the pots -- lots of water -- will remedy this particular situation. But you can try it.

Understand that this is one of those (many) live-and-learn lessons of gardening we all learn. It's one that you will remember for a long time. (And, if so, congratulations, you're making progress!)

Shazaam,

I use a mix of 60-70% pine bark mulch, 20-30% peat moss and 10% perilite or coarse pavement sand. Ive had good results with both sand and perilite just alittle weight difference. To that I add a tsp of sulfer and about 4 to 6 oz. of Microlife 6-2-4 fertilizer. Mix it all up and let it rip baby! That is for 15 gallons of potting mix. Ive had my ups and downs with to much sulfer as well. Anyone growing blues will deal with it eventually using it in pots. There is definatly a learning curve to grow these things.

Flushing the pots with tap water will work. I did it to 17 potted plants last summer from adding to much sulfer in the starting mix.

I use a mix of 60-70% pine bark mulch, 20-30% peat moss and 10% perilite or coarse pavement sand.

Have you tried it without sulfur? I ask because I've been using a very similar mix for several years now, and, so far, I haven't used sulfur and haven't had any serious problems as a result. At the same time, I sometimes consider adding just a little bit as a preventative since sulfur does require some time to work. If I decide to give it a try, a teaspoon sounds like a safe place to start...

Back to your problem, ahajmano, what kind of potting mix did you start with? Since you're in CA, perhaps something like Dave Wilson Nursery recommends? Or was it just an all purpose potting mix?

Shazaam,

Ive always added sulfer to my mix. I believe you are right though. I could probably not use it at all because the intial potting pH sould be sufficient. Using rain water will keep the pH from drifting as well. I havent ever had to add any more sulfer to any of my plants after planting in raised beds or pots and some are going on 4 years now.

Measured the PH today. It's at 6.0 (see image). The blueberry I. Question was grown in standard miracle grow potting soil.

So out of frustration, I went out and bought a 1 gallon misty and sunshine blue. I put them in 15 gallon pots with 4 parts peat moss, 3 parts redwood compost, 2 parts kitchen scrap compost and 1 part perlite.

Lets try this Again...

In the meantime, I will be patient and flush the existing ones.

Picture of PH

Why do you feel you need to flush the existing bushes?
Your pH is too high. Your bushes are stressed, but they're a long way from dead. Get some iron sulfate. Add two or three tablespoons and water it in. Wait a couple weeks see how the soil and plants are responding and repeat. It takes much more iron sulphate to lower the pH than sulphur, but it acts quickly and provides iron. Slowly bring the soil pH into range and you can save these plants.

I agree with Blueberryhill. It took some time for the plants to get to this point and will take some time for them to get back to green and happy. Just get the PH down. The iron sulfate or you can try some vinegar water for a quick fix.

I have used that PH test kit before and no matter what i did, it always read 6-6.5. Pure vinegar 6-6.5. maybe I got a bad or very old kit? Who knows?

This post was edited by Drew51 on Fri, Apr 26, 13 at 9:08

The reason that I suggested bromocresol green indicator solution, for soil pH testing, is that the results are more easily read. The solution will be yellow, blue, or green. My guess is that your irrigation water is high in dissolved limestone, and it is raising the pH of the blueberry pots. Bromothymol blue indicator solution can be used to test the pH of your irrigation water. If you are using a municipal water supply, they should have an annual water quality report on file, and this would give the hardness, and also the pH. It is clear that you are living in an area of the world where there is limestone present, and it will be necessary to measure soil and water pH in order to grow blueberries. With regard to sulfur, as a soil additive, the process depends on bacteria that are normally found in the soil. If a blueberry shrub is set up in a pot filled with "soil-less growing medium," it is not clear to me that the bacteria required for sulfur metabolism would be present. You might have to resort to pre-treating your water with sulfuric acid, to lower pH to around 5, in order to grow blueberries successfully. There are many people doing this, it is not too hard, but care is needed. Too much acid will kill the shrub for certain. Despite all of the chemistry and complexity above, growing blueberries is actually pretty easy, once you get the pH right.

I will have to find some bromicresol, and buy some distilled water to utilize my existing PH kit. Can I used distilled vinegar in place of H2SO4? Anyone have a dilution vs. PH scale?

Can I used distilled vinegar in place of H2SO4?

Citric acid, phosphoric acid, sulfuric acid, acetic acid...any acid will do. Sulfuric is often recommended since its effect is permanent (whereas organic acids like acetic only temporarily tie up bicarbonates since they're metabolized by soil organisms), but I've done fine with vinegar over the years.

Anyone have a dilution vs. PH scale?

Bicarbonates are the monkeywrench here. Since bicarbonate content varies between water sources, the amount of acid required to neutralize them and lower pH will vary. For example, my well water has a pH of approximately 7, but I have to use at least 4 fl oz of vinegar per gallon to drop the pH below 6. Others are able to do the same with just a single tablespoon.

This post was edited by shazaam on Sat, Apr 27, 13 at 9:31

Just to jump in here FWIW, I use a very similar container mix to shazaam. Basically pine bark mulch, peat, and perlite, and NO sulfur. This is year 3 with some of my plants. I add 1 tablespoon of white vinegar per gallon of water. So far so good. I am anxious to try the distilled water pH test though.

I had the same problem with a bush someone gave me. I re-potted it in in Miracle Grow acidic potting soil. I started watering it with Miracle Grow for azaleas, and it started growing great. In 6 weeks, all the color came back.