Blueberries fertilizing during fruiting?

Been looking and searching for topics covering fertilizing blueberries during the fruiting stage but found none.

Once the flower buds start to turn to berries, is there any recommended way to fertilize them? Thanks.


What was your way of fertilizing them before they fruited?

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Best to apply small amounts of fertilizer early before bloom. And maybe a little late spring.
Ammonium sulfate, not ammonium nitrate, being much preferred for the nitrogen.
Late season fertilization will reduce next season buds (opposite of strawberries), and also make them more tender going into winter.


Before leafings and flowering’s I did apply holly tone granular fertilizer. Perhaps that is plenty enough. Was just wondering if fertilizing during fruiting would be any more helpful for the plants and if anyone have a preference way to do it.

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I usually feed mine,when they start growing,about every 3-4 weeks,until August.


I agree with that Bradybb so long as it’s in moderation…several scattered applications are better than a big one…but a big one is safest before they leaf out.

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The best fertilizer is probably Berry-tone.


It is balanced at 4-3-4. It also contains Calcium and Sulfur. Azalea-tone is about the same and I can’t tell the difference. Tomato-tone has even more P and K, but less Sulfur. Holy-tone is good too. But it has less Sulfur.

They are all organic, slow release fertilizer. It is always recommended to mix with Ironite and Sulfur to amend the soil maintain the low Ph.


Definitely a safe choice…although on a commercial scale may be too expensive an option.

If you talking about commercial fertilizer, I recall some folks use aluminium sulfate and other in-organic fertilizers. Then some replace it with ammonium sulfate since people try not to use aluminium in food items.

But for most of us home gardeners, we prefer to use the organic fertilizers. That one big of Berry-tone or Holy-tome or Garden-tone may cost like $25 or so. But it is good enough for almost everything for one year or two. Sure we can mix with blood meal, bone meal, element sulfur etc. Not sure if that is much cheaper.

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Perhaps that’s a good idea. But, let’s suppose you had just 5 acres and no income from any source and your entire livlihood was coming from your farm. Balancing your check book every month would get a lot more complicated with 4 pound bags of organic fertilizer costing $25.

So, while a hobby farm that is supported with discretionary money that might otherwise be spent at a sit-down quality restaurant or tickets to a ballgame or concert might be able to operate via no commercial fertilizer (or spreading of cow or horse manure)…
those ready-to-use bags of organic fertilizer at $25 for enough for 6 plants doesn’t work out economically for anyone that needs to profit or at least ‘break even’ on their little piece of paradise.

So, listing options is great…but pushing organic as if one size fits all seems political more than it seems gardening. See how easy it is to go from fertilizing blueberries during fruiting to a discourse on organic vs commercial fertilizers?

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@ BlueBerry

Yes very true.

I’ve heard some farmers in India, China and other countries keep two sections of their farm land. The big fields are for the commercial farming and the small parcels are for own farm garden. Of course we know the rest of the story.

I did not say that the Tone fertilizers are the ones for all home gardeners. But several people mentioned them. For home gardeners to truly save money, we can collect all the leaves and make them into leaf mold. That is how native blueberries survive in our NJ pine barren. There is no cost at all other than a lot of sweat and long wait time.

We can also turn kitchen craps into home made compost. Mix with pine needles for more acid content. Everyone can do that.

Since I own some woodland, I can scrub forest floor to get some forest humus. It is free, but not everyone can do that. It is rich too since deer frequent that area.

There are many ways we can use as fertilizer. The question is the cost of $ and time. Home gardening is more a hobby for most people here. And most of us probably never make $$ if you add all the cost, not even the labors involved. But we still get the enjoyment out of this hobby. And we like everything we grow in our yard and our garden.


For blueberries leaf mold is an excellent choice. Or any kind of compost or cheap manure is a great economical alternative to make the soil fertile just don’t forget to add sulfur if your soil is too alkaline. As far as the comment on Espoma fertilizer: number one don’t buy 4 lb bags buy the large bags 25 lb I think or 50 lb. Google that brand fertilizer online and look for a sale that is happening. I bought a large bag at a True Value hardware for less than I could buy the 4 lb bag at one of the big box stores. This is not an advertisement for True value I’m just saying shop around and you can get a better deal on the large size bags. If you’re trying to make money off of your truck patch though go with the cheap or free manure, leaf mold and for blueberries don’t forget to add the sulphur because blueberries needed acidy and much of this country soil is too alkaline for blueberries unless you amend it with plenty of elemental organic sulfur.


Good explanation RedSun.
I guess I was a bit grumpy for no reason…
but certain points and agendas can be pushed and
if I push back, my posts get flagged, and
it’s irritated me that such is the case.
There’s nothing wrong if you want
to spend more to have a pretty garden than you get in return…afterall,
having a healthy state of mind from working in your own soil and with your own
plants is quite medicinal…not everything is about dollars.
(But, some people don’t have discretionary money, and I always try to see things from their perspective too.)


Actually I’ve been lazy with fertilization. I mostly fertilize my fig plants. Maybe I should do other plants too. I’m mostly a compost type of person.

I think I should really spend some time to harvest some of the forest humus. I dug a little in the woods and the top soil is very black, very different from my red soil.

That area far away from my yard. So I’m not worried about disturbing the woods.

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I have used Holly Tone on young Blueberry plants but it leaves a terrible smell on your hands and clothing that sticks around a long time. Even after washing your gloves you can still smell it. It’s a little less than $1/pound in a big bag but its only about about 5% N but you get the P and K too

Feather Meal is a more affordable form of organic nitrogen About 15% N for less than $1/pound.

Typical recommendation for commercial blueberries is around 50 pounds of N/acre each year, half in the spring and half after harvest but I use a lot less especially on my Rabbiteyes.

I have not found a valid field trial that showed economic value in the beneficial bacteria fshown on the label for blueberries but I found one that showed no economic improvement.


I resemble that remark! As my garden grew I found the tones to be too expensive. I went back to commercial alternatives. I need more than a 20 pound bag. Not really any good choices in a complete fertilizer. I still use Hollytone but supplement it with AS products. I like to keep urea around too when I don’t need to lower pH. Such as in Miracle Grow for acid loving plants. Cheap enough, works great.

I agree no benefits for blueberries, they need a specific fungi, well one is the best, but 2 or 3 others exist. As far as know at present this Mycorrhizal fungi is not sold anywhere for the home market. Once in awhile a company will offer it, but they keep going out of business or stop making it. I heard the strain is hard to keep for commercial production. I forgot the specific fungal names, lost my link to that info.

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Appears I kept a text of the info from a discussion I was having.
Blueberries are in the heath family, ericaceae. This means that they must have symbiotic fungi to live properly, being so adapted to having mycorrhizae as to not have root hairs. I did a bit of quick research, and it turns out the issue is weirder than I first thought. Plants of the family ericaceae, and specifically blueberries have a type of mycorrhizial association called ericoid mycorrhizae, typically fungi of the genus Hymenoscypus or Rhizoscyphus, and most typically Rhizoscyphus ericae. And without digging deep into weird places I doubt I could get culture of that fungus. If I were you, I would try and get a bit of soil/root mass from a thriving old established blueberry / wild vaccinium / cranberry / heath / rhododendron / heather plant in decending order of preference; and try and get said soil around the roots as a sort of seed to hopefully get the inoculation. No hurry, but the fungus is how they get their food to a large degree, unless they are in a nursery getting weak chemical fertilizers in the water, in which case they don’t even need the fungus and it tends to atrophy unless fed.

Links no longer work. I long ago inoculated my soil when this product was available.
You need this fungus Rhizoscyphus ericae


No, really, I think late fertilization might be fine if you’re trying to push the size of the plant to fill a spot or something…and you aren’t concerned if all the new growth fails to set fruiting buds for next year. Still–don’t over do it, the roots are small, tender and near the soil surface.

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Sometimes we buy store blueberries. They are large sized, but taste so bland. I attribute that to fertilizers. The same principle with growing grapes. Our soil is too rich and too much water for wine grapes.

So personally I do not fertilizer blueberry much, or very light in spring and maybe one more time in summer, shortly after fruiting. I do not fertilize them in fall since they need to be prepare for winter. And almost all my gardening is organic. I stop fertilizing my lawn several years ago.


I’ve not tried many blueberries I don’t like. Even the ‘bland’ ones aren’t bland if they are all you have at the moment.