Have a Question? Ask Our Pros!
The Peters Professional Acid Special 21-7-7 (E99330) is a water soluble fertilizer that helps in producing healthy and acid loving crops. It has a formula with high potential acidity that lowers pH levels or offsets high water alkalinity in growing media. This fertilizer is the excellent choice for water type 3 and 4. It also contains a great range of micronutrients that's essential to promote greening.
| Active Ingredient | Total Nitrogen - 21% Available Phosphate - 7% Soluble Potash - 7% Magnesium - 0.6%, Sulfur - 13.0%, Boron - 0.0262%, Copper - 0.0262%, Iron - 0.15%, Manganese - 0.05%, Molybdenum - 0.01%, Zinc - 0.05% |
|---|---|
| For use in | Acid Loving Crops |
| Application |
1 tsp per 1 gallon of water (1 tbsp per 2 gallons of water) * Can be tank mixed for watering cans and spray tanks except injectors * See label for complete application instructions |
| Color | Blue |
| Material / Construction | Ammonium Phosphate, Ammonium Sulfate, Urea, Potassium Sulfate, Magnesium Sulfate, Boric Acid, Copper EDTA, Iron EDTA, Manganese EDTA, Ammonium Molybdate, Zinc EDT |
| Special Features | Water Soluble Fertilizer |
| Shipping Weight | 25.26 lbs |
| Manufacturer | Everris Na Inc. (Mfg. Number: E99330) |
| UPC | 848264006792 |
Produce healthy acid-loving crops with this formula’s high potential acidity that offsets high water alkalinity or lowers pH levels in growing media.
Product Properties:
Potential Acidity .......................... 1518 lbs calcium carbonate equivalent per ton
Conductivity of 100 ppm N ......... 0.52 mmhos/cm
Maximum Solubility ..................... 4 lbs/gallon
![]()
Good response
By Charles on 06/11/2016
We have used Acid Special 21-7-7 for many years on blueberries in pots in the greenhouse with excellent response It gives a rapid response before a dry, slow release becomes available. Order and shipp…
Read Full Review »![]()
The Blueberry Person
By Norm on 09/15/2022
This fertilizer is excellent for blueberries. When used every 10 days during the growing season, it is a great stimulant of new plant growth, which increases fruit yield the following year.
![]()
Great Stuff
By Plant on 03/21/2025
Peters is the Best Fertilizer in the world. But the Review must be 50 characters long. LOL I thought Great & Best would be enough words. Dr. LWB
The product label for Peters Professional Acid Special 21-7-7 states you use 1 tsp of product with 1 gallon of water equals 245 ppm (Parts per Million) of Nitrogen.
Peters Professional Acid Special 21-7-7 would not help in eliminating bamboo. Bamboo is very tough to kill and will take repeat applications using a non selective such as Roundup QuickPro. Bambo…
Read Full Answer »