Avoid fertilizers with nitrate nitrogen. It should say on the bag whether it's nitrate, urea, or ammoniacal nitrogen. In KS you'd likely be better using ammonium sulfate as your nitrogen source. If you need the other nutrients get some designed for acid loving plants. I recently bought some Miracid 30-10-10 by Miracle-Gro. It has 3% ammonical nitrogen and 27% urea nitrogen plus trace elements.

Nitrate nitrogen damages blueberry plants. Ammoniacal nitrogen lowers soil pH and is ideal for blueberry on high pH soils. Urea nitrogen is ideal for blueberries on soil with low pH.

This post was edited by fruitnut on Tue, May 14, 13 at 13:56

Also,another Blueberry grower posted about friends that used some that had Muriate of Potash in it and it killed the plants.The one to use has Sulfate of Potash(Potassium Sulfate).
Brady

In case we haven't made it clear 10-10-10 could contain both nitrate nitrogen and potassium chloride = KCL = muriate of potash. If it has either one don't use it on blueberry.

I use the following at bud break and post harvest...

http://microlifefertilizer.com/products/microlife-azalea-6-2-4/

Never tried anything else.

I would suggest you determine your soil ph before deciding on a fertilizer. PH is critical for blueberries.

RM

Another alternative to 10-10-10 is cotton seed meal which is organic,slow release, and works great. It is recommended for blueberries in my area, I bought a 40lb bag from a feed and seed store for 25 bucks.

Some good advice all, thanks. I checked the 12-12-12 I had and sure enough, it had the phrase 'muriate of potash' on it. So that bag's a no go.

Bamboo_rabbit, where are you getting your ammonium sulfate from? None of the box stores in my area carry it besides the tiny super expensive bags, and the one farm supply store I know of doesn't have it either. I really don't want to go the online route as large bags of fertilizer tend to have large shipping costs.

You're never going to get complete consensus on blueberry care and feeding, but there are plenty of instructional sources on the Internet from reliable vendors for you to follow. I'm growing SHB blueberries in pots, with very good results, and I most likely use a much lighter fertilizer hand than most. Note that BB are sensitive to over-fertilization. So whatever you decide to use, you will be fine if you err on the side of caution by treading lightly.

That said, I've never seen 10-10-10 recommended anywhere, maybe because it isn't enough of a super-charger for those that prefer high N fertilizers, and isn't organic for those that lean in that direction. It might lack micro-nutrients as does ammonia sulfate, which is crack cocaine and steroids for plants. I wouldn't rule the 10-10-10 out altogether, but I think fruitnut and bradybb provided some valid considerations.

I'm growing SHB blueberries in pots, with very good results, and I most likely use a much lighter fertilizer hand than most.

I take it that you're more or less following the potting mix and fertilizer recommendations in the Four Winds guide, mrclint? I have quite a few container blueberries, and I'm always curious about what works for other growers. Which particular fertilizer(s) do you use, and what's your application rate?

For in ground blueberries, languard, I'd lean toward something organic, like cottonseed meal, alfala meal/pellets, etc. Pretty much any organic nitrogen source is going to break down into ammonium nitrogen first, and, in general, blueberries utilize ammonium nitrogen much better than nitrate (the ammonium form is more prevalent in the acidic soils to which they're adapted because low pH inhibits the activity of microbes that convert ammonium nitrogen to nitrate). I really like alfalfa meal since it provides organic matter to feed soil microbes, a nice balance of all of the macros (NPK), and an assortment of trace elements.

"I take it that you're more or less following the potting mix and fertilizer recommendations in the Four Winds guide, mrclint? I have quite a few container blueberries, and I'm always curious about what works for other growers. Which particular fertilizer(s) do you use, and what's your application rate?"

Hopefully this won't hijack languard's post, but since you asked... :)

I started my blueberry trials a few years back with DWN's Blueberries In Containers directions for potting them up. In the search for complete general care directions, I began loosely following the Four Winds Growers sheet for everything else. My approach has been to stick with reliable and accountable vendor recommendations -- because I can vote with my dollars and rate them on G@rdenw@tch, etc.

Be that as it may, I started out with Miracle-gro azalea formula according to directions, applied at least a handful of times spread out during the growing season (starting when they leaf out a bit in spring, never on a hot day, and ending in October). They are also sitting next to an East facing fence so they only get morning to mid-day sun. No acidification of my water, just straight from the hose. I will continue to use the M-G until something better comes along, as this is the rare situation where I am growing in containers and/or not fully organic.

The idea of planting in ground organically, with a pH hardy variety (Sunshine Blue?) is worthy of a trial. :)

Languard,

I get my ammonium sulfate from Helena chemical. They are a national company so they may be near you....you might want to put your location in your profile. Ammonium sulfate is not only a fertilizer but is a tank add to boost the effectiveness of herbicides like roundup so it is used widely. Find out where your farmers buy their chemicals and they will have it.

While the plants need all nutrients they really only need nitrogen on a regular basis. Once you see how the plants grow on it you will never go back to anything else.

Shazaam, curious to hear your experiences as well, and if you are following a particular set of recommendations (it's always good to know who is experimenting, following a set of directions, or taking a little bit of knowledge and then winging it). It appears that much of the university recommendations are not well suited to home growers, while some message board recommendations are helpful, some observations and comments are self-serving and way off-base. :)

The idea of planting in ground organically, with a pH hardy variety (Sunshine Blue?) is worthy of a trial. :)

Funny you should say that...last spring, I planted a Sunshine Blue (for just the reason that you mentioned) in my front garden in a shallow (6") raised bed filled with a pine bark/peat blend. The soil underneath is unamended clay with a pH in the 6.5 range. I haven't acidified the soil (intentionally), and I've fertilized the bush modestly with cottonseed meal, alfalfa pellets, and a little bit of Peaceful Valley Farm Supply's Prime Start Booster Blend. So far, so good -- I've seen no indications of nutrient problems, and it's growing well.

...curious to hear your experiences as well, and if you are following a particular set of recommendations...

My other blueberries (nearly 30 now) are all in containers, and I owe tapla in the container forum a lot of credit for my success with them. As you might already know, his 5-1-1 mix (bark/peat/perlite) is essentially the same as what Four Winds recommends, and it's served me well. As he suggests, I add one tablespoon of gypsum to each gallon of potting mix (for Ca), 1/8 to 1/4 tsp of epsom salt to each gallon of irrigation water (for Mg), and I fertilize weakly with MirAcid at every watering (typically about 1/4 tsp per gallon). Because I have hard water, I also add vinegar to my irrigation water.

I've also begun experimenting with a peat-free potting mix (85/15 bark/perlite), organic fertilizers (primarily cottonseed and alfalfa meal), and I have one Brightwell rabbiteye that's serving as a test subject for the suitability of Osmocote Plus (a significant portion of the nitrogen is in nitrate form) for blueberries. Can you tell that I like to grow and talk about blueberries? I find them endlessly fascinating... :)

Can you tell that I like to grow and talk about blueberries? I find them endlessly fascinating... :)

Well said Shazaam;) I'm trying to thin some of my plants out now. Had up to 55 at one point last year now it's down to 35 and dropping. They are fascinating to say the least! I've only used Micro Life 6-2-4 like Sunjunkie. We are both in Houston and that's the only place to get it I guess. It's a shame too cause the fert is fantastic!!!!!

Well said Shazaam;) I'm trying to thin some of my plants out now. Had up to 55 at one point last year now it's down to 35 and dropping.

That must be tough! I can't seem to resist adding more every year, but I'll have to begin thinning as well if this continues (and it will). I keep trying to come up with a plan to turn my hobby into a business so that I can spend all day every day with my blueberries (and figs...can't neglect the figs).

Don't use 10-10-10, it will kill them possible. It won't do them any good thats for sure. Use an acid fertile. Coffee grounds are ok, and mulch with "Pine Bark" its naturally acidic.

I have had rabbiteye blue berry plants for over twenty-five years & never use chemical on them.

I use coffee grounds the first year, nothing after that.

All of my plants spread by sucker after the third year, I do have one plant that will not spread, think it called Prime. I have over 100 plants now & pruning as well as transplanting small sucker is a job.