Top 9 Potassium Fertilizer for Plants – Garden Fertilizers

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1. Down To Earth All Natural Fertilizers


Down to Earth Organic Langbeinite Fertilizer Mix 0-0-22, 5 lb

Down To Earth All Natural Fertilizers #ad - Potassium contributes strongly to overall plant health by regulating internal processes. Down to earth langbeinite 0-0-22 is a naturally mined crystalline mineral that supplies the water-soluble sulfate form of three vital plant nutrients: potassium, magnesium and sulfurs.

Keep it real, keep it lightrail; Solidly made in the USA since 1986. Potassium deficiencies lead to weak stalks and immature roots, leaving the plant susceptible to insects. Since potassium makes up part of the fluid of the plant, it is found throughout plant tissue, meaning plants need a strong source of potassium as they grow. Its maximum chlorine content is less than 3. 0 percent, minimizing the potential for fertilizer “burn, ” and its neutral pH does not alter soil activity.
BrandDown To Earth All Natural Fertilizers #ad
ManufacturerDown to Earth #ad
Height10.8 Inches
Length3.5 Inches
Weight5.25 Pounds
Width8 Inches
Part Number07852

2. Down To Earth All Natural Fertilizers


Down to Earth OMRI Organic Solution Grade Potassium Sulfate 0-0-50, 1 lb

Down To Earth All Natural Fertilizers #ad - Designed for efficient delivery and immediate uptake, fertigation, this 200 mesh powder can be used in reservoirs, drip irrigation or spray applications.

Contains potassium k, magnesium mg and sulfur S – three of the essential nutrients that plants require to achieve optimum growth and reach their maximum potential. In a balanced ratio and in the highly available water-soluble sulfate form, we offer a high performance solution grade powder that growers can apply with confidence. Listed by the organic Materials Review Institute OMRI for use in organic production. Performing a complete soil or plant tissue analysis or using a home soil test kit before application is recommended.
BrandDown To Earth All Natural Fertilizers #ad
ManufacturerDown To Earth All Natural Fertilizers #ad
Part NumberDTE-FERT-SOLU-Potassium-1lb



Soil, ENVY Bloom Trigger Professional Grade 0-10-11 Phosphate + Potassium Supplement for Bloom Stage in Hydro, Coir

ENVY #ad - High phosphate content - our bloom Trigger is scientifically formulated to supply Phosphorous and Potassium to your plants exactly when needed for superior budding, flowering and bulking.

Great for soil, hydro or coir - our bloom trigger is designed to be effective across all major growing mediums in its ability to elicit prolific budding, flowering, and aromatic terps such as Limonene. Better with envy - our bloom trigger works well with any and all supplemental nutrition; but for optimal results, consider using our ENVY CalMag+ Fe and our Base A/B nutrients together.

Super concentrated - only 1-2 teaspoons 5-10ml are needed per gallon of water, making our Bloom Trigger both highly-effective and highly-economical. Prolific flowering - our bloom trigger provides a highly-available source of potassium and phosphorus to drive bud and flower production while being supported by supplementary Vitamin B-1.
BrandENVY #ad
ManufacturerNational Liquid Fertilizer #ad

4. EZ-gro


Tomato Fertilizer by EZ-gro is a High Potassium Fertilizer for Your Tomato Plants | Field Tested Tomato Plant Food for Vegetables | A Concentrated Liquid Tomato Plant Fertilizer | 1 Quart

EZ-gro #ad - Concentrated liquid fertilizer - Add to water for the most effective and accurate nutrient delivery system to your tomatoes plants. Free mearsuring cup - all of EZ-gro fertilizers come with a free measuring cup for precise and accurate product application.

It produce vibrant green leaves, strong vines and abundant fruit. Enhanced micronutrients - supplies the nutrients need most by tomatoes and other fruiting vine vegetables. High phosphorus content - encourages rapid root generation which eliminates transplant shock when used in a transplanting solution as a fertilizer for tomato plants. Ideal fertilizer - ez-gro 15-20-28 is the ideal blend of tomato food for encouraging healthy plant growth and a strong root system.
BrandEZ-gro #ad
ManufacturerEZ-gro Products #ad
Height8 Inches
Length5 Inches
Weight2 Pounds
Width2 Inches

5. Element Nutrients


Heavier Harvests 250g, Flower Fuel 1-34-32, 250g, The Best Bloom Booster for Bigger

Element Nutrients #ad - Over 40 proprietary ingredients go into every jar of Flower Fuel. It works great with any base nutrient including all popular 2 and 3-part nutrients, coco, and in any soil, hydroponic or aeroponic system.

Among these are powerful nutrients, vitamins, essential organic components, amino acids, hormones, and every single micro and trace element you need to get your best harvests yet. Consists of nutrients, vitamins, amino acids, and organics. Formulated to achieve larger, denser and heavier harvests with more essential oil and resin content. Flower fuel is a 100% hydroponic-grade, soluble bloom fertilizer. Treats 200 gallons of water! try flower fuel Today for Bigger, Better Harvests! Flower fuel is a super-premium bloom booster. That means better looking, more valuable crops for you.
BrandElement Nutrients #ad
ManufacturerElement Nutrients #ad
Height3 Inches
Length3 Inches
Weight0.55 Pounds
Width3 Inches
Part NumberFF250G



RAW- Potassium Health Element for Plant Growth/ Increase Fruiting and Flower Production/ Plant Feeding Supplement/ for Indoor /Outdoor Use/ Hydroponics- 2 oz

RAW ELEMENTS #ad - Raw potassium- easily mixes into water and is completely soluble. Raw potassium is ideal for boosting Potassium K levels, treating deficiencies & creating optimal recipe solutions. Works in conjunction with all nutrient & feeding programs.

This is the highest concentration of natural Water Soluble Potassium available to the home gardener. During fruiting & flowering, large amounts of potassium are used by the plant in a matter of days which can lead to K deficiencies. Apply as needed. Where to use: great for use in soil, hydroponics, or other growing media.

Directions for use: add1/16th to 1/8th tsp per 2 Gallon in the reservoir for irrigation. Benefits: potassium is known as the health Element. About: raw potassium contains 50% water soluble potash derived from potassium sulfate. Increases sap and sugar content during later stages of fruit and flower. It helps maintain water and nutrient movement within the plant.
ManufacturerNPK Industries #ad
Height6.5 Inches
Length4.25 Inches
Weight0.13 Pounds
Width1 Inches
Part Number717909

7. Supreme Growers


Simply Silica 8oz Concentrate by Supreme Growers Potassium Silicate Liquid Fertilizer Promotes Growth of Strong Plant Tissues Improves Natural Resistance to Environmental Stresses Makes 47 Gallons

Supreme Growers #ad - Call our hotline at 614 745-1945 with any questions. Simply silica improves a plant's natural resistance to environmental stresses, including heat and drought. Use simply silica as a soil drench or foliar spray once a week from start of vegetive growth throughout flowering and fruiting.

It will not clog drippers. Simply silica is designed to supplement your existent nutrient program, not replace it. The 8oz concentrate of Simply Silica makes 47 gallons of ready to use product. Simply silica is a liquid fertilizer formulated with potassium Silicate that promotes the growth of strong plant tissues. Silica is a mineral supplied to plants as a nutrient that provides rigidity and structural endurance for crops. Silica increases root growth, boosts yield, and enhances crop quality. It is safe for resevoirs.
BrandSupreme Growers #ad
ManufacturerSupreme Growers #ad
Part Number1

8. JR Peters


1.5 lb., JR Peters 51324 Jack's Classic 12-15-30 Tomato Feed

JR Peters #ad - High potassium Assures A Good Crop. Produces vibrant green Leaves, Strong Vines And More Fruit. No assembly Required. Optimum combination Of Nutrients For Fruiting Vine Vegetables.
BrandJR Peters #ad
ManufacturerJR Peter's #ad
Height5 Inches
Length5 Inches
Weight1.5 Pounds
Width5 Inches
Part Number51324

9. Easy Peasy


Triple Super Phosphate 0-46-0 Easy Peasy Plants 99% pure 5lb

Easy Peasy #ad - More economical than any other phosphate. Helps root growth, fruit, and flower formation. Enriched source of Phosphorus. Granular for easy application and feeds plants quickly. Use only 1 cup per 100 square feet at planting time and every 6 weeks.
BrandEasy Peasy #ad
ManufacturerEasy Peasy Plants Inc. #ad
Part NumberPD-32289