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Soil Acidifier

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  • 2 or more: $9.99 each
Item #H24344, 13 Ounces (by weight)


Lower soil pH to increase nutrient intake. Alkaline soil can keep certain acid-loving plants from absorbing the nutrients they need to grow well. Blueberries require acidic soil, and so do other plants such as blue hydrangeas, cranberries, and lingonberries. This specially formulated mixture creates the perfect soil conditions for those plants to really grow. Use as directed, ideally prior to planting. One cup of soil acidifier covers one square yard of planted area. For existing plants, sprinkle soil acidifier evenly over root zone and work into soil. Contains sulfur.

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Questions & Answers

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Browse 6 questions Browse 6 questions and 21 answers
Why did you choose this?
Stark Bro's Store
need it for my blueberries
John M on Sep 29, 2016
I understand blueberries need lower pH soil.
Rachel W on May 26, 2016
need it for my blueberries
John M on Sep 29, 2016
My lemon tree needs this.
PEGGY S on Aug 29, 2016
I understand blueberries need lower pH soil.
Rachel W on May 26, 2016
I live in a limestone area, so we need more acid for blueberries.
AMY K on May 6, 2016
I believe this is important for the plant
Louetta T on May 3, 2016
for blueberries and azaleas
James B on Apr 10, 2016
needed for blueberry and cranberry plants
Gregory C on Apr 6, 2016
I have used this for years on my blueberries; I know blueberries need an acidic environment.
MARY L on Mar 19, 2016
Better Blueberries.
Jonathan A on Mar 16, 2016
need for my 12 blueberry bushes
GEORGE R on Mar 13, 2016
Definite need for blueberries. Can be difficult to find in stores in my area.
MARY R on Mar 10, 2016
I want to give the blueberries a fighting chance. I also grown azaleas and hydrangeas so I need to keep the soil acidic.
Mary S on Mar 1, 2016
A must for proper blueberry plant maintenance.
Barbara I on Feb 25, 2016
My lemon tree needs this.
PEGGY S on Aug 29, 2016
I live in a limestone area, so we need more acid for blueberries.
AMY K on May 6, 2016
Planning to purchase both the Soil Acidifier and the 12/12/12 fertilizer. What's the best regimen to use both in the garden as to timing of applications and amounts needed per treatment?
Dave V on Mar 20, 2016
BEST ANSWER: SOil acidifier should be used the previous fall if possible. At least as early as you can. The process by which soil pH is raised or lowered takes a few months. Add lots of peat moss to your blueberry beds BC it has low pH to begin with and holds moisture..
As to applying fert, apply around drip line 6 in from base at the time of new growth in spring. Then every six weeks till mid summer.
How do you apply this to the plant? Is it to be mixed with water or do you just spread the powder around the plant?
Quinn K on Apr 1, 2016
BEST ANSWER: The directions mention to incorporate it into the soil at the time of planting. They do not specify how often this needs to be repeated or if a target pH should be achieved. I have been mixing it into and on soil around the plants, but mine are in pots.
So what is in this?
Deb R on Apr 5, 2016
BEST ANSWER: Garden sulfur.
My soil PH is 7.9-8.0, will I need extra soil acidifier to lower it to recomended levels or will the 1 cup per sq. ft. work?
Harlon H on Jul 5, 2016
BEST ANSWER: Garden sulfur lowers soil pH over time, so it's best to follow the directions and then test the soil pH again. Repeat as needed. Planting in containers is always an option while you amend the native soil.
The directions say use 1 cup of acidier to 1 square foot of soil - is this the traditional 1 cup (8 ounces) or the cup that comes with the acidifier kit?
C K on Jun 10, 2016
BEST ANSWER: The instructions refer to an actual cup. The utensil that comes in the package is just a scoop for your convenience.

Customer Reviews

4.3 / 5.0
3 Reviews
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Great for Blueberries
My new blueberry plants were not growing at all. The leaves were red. I applied the acidifier by sprinkling it on the ground each of the last 2 falls and the leaves are now green and plants are growing... a little. The better solution is to work this product into the soil when planting blueberries.
May 8, 2016
over 2 years ago
Perfect blend for my berries. Must have for any berry grower
May 19, 2016
1 year ago
Soil Acidifier
Haven't seen results yet in lowering my 7.0 soil. Will wait a it longer, unless you think it's ok to add every couple of weeks to reduce the alkalinity of my soil. Please advise, thank you, Dianne
March 12, 2016
12 months ago
Response from Stark Bro's
Thank you for your feedback. It does take some time for the soil to adjust with the acidifier. Yes, you can go ahead and add every couple of weeks until you see it start to decrease.
March 13, 2016
Brenda HStaff
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