Jar Testing 101

The W-A-L-E-S Method for Testing Tank Mix Compatibility

Always perform a jar test before mixing products in your spray tank to ensure compatibility and prevent costly application problems.

Five-stage jar test showing carrier, products added in sequence, agitation, and compatible versus separated mixtures
A jar test previews how a proposed tank mix behaves at small scale. A uniform mixture is encouraging; layers, clumps, sediment, or separation mean the combination needs review before it reaches the tank.

What is the W-A-L-E-S Method?

A proven sequence for mixing agricultural products safely and effectively

W

Water Soluble

Pouches

A

Agitate

Then add others

L

Liquids

Flowables

E

Emulsifiables

Concentrates

S

Solubles

Surfactants

Jar Test Strategy

Product Mixing Order & Amounts

Follow this sequence and use these amounts when testing in a quart jar

Swipe horizontally to see the complete mixing table.

OrderMaterial TypeAmount to Add to Jar
1Water Soluble Pouches1 Tablespoon/lbs
2Wettable Powders1 Tablespoon/lbs
3Dry Flowables/Water Dispersible Granules1 Tablespoon/lbs
4Suspension Concentrates/Flowable Capsule Suspensions1 Teaspoon/pint
5Emulsifiable Concentrates1 Teaspoon/pint
6Soluble Liquids1 Teaspoon/pint
7Soluble Powders1 Teaspoon/lbs
8Surfactants, Oils, Remaining Adjuvants1 Teaspoon/pint
9Fertilizers (Last)1.1 grams**/lbs

Jar Testing Steps

1
Add Carrier

Add 1 pint of carrier (water or liquid fertilizer) to a quart jar. This ensures there is enough carrier in the tank to effectively dissolve and incorporate the products into the solution.

2
Add Products in Order

Add each product to the jar in the ratio and order that you will use when adding them to the spray tank. Employ the W-A-L-E-S sequence during tank mixing.

3
Shake, Wait, and Inspect

Fill the remainder of the jar with carrier, then shake and invert it for 30 seconds. Allow the solution to stand for 30 minutes.

Compatible Mixture

No precipitates, sludges, or separations present after 30 minutes

Incompatible Mixture

Visible precipitates, sludges, separations, or clumping

Common Tank Mixing Mistakes to Avoid

No Test

Combining inadequately tested formulations without jar testing first

New Mixtures

Preparing new mixtures using multiple products without testing compatibility

Out of Sequence

Mixing products in the wrong order, not following W-A-L-E-S method

Insufficient Water

Adding products when there's not enough water or carrier in the tank

Not Dissolved

Not waiting until products are fully dissolved before adding more

Cold Water

Mixing in cold water without considering temperature effects on solubility

Little Agitation

Mixing with either too much or too little agitation

Water/Fertilizer Swap

Not considering differences when substituting fertilizer for water as carrier

Label Ignored

Not following product label directions and recommendations

Always Test Before You Mix

Taking 30 minutes to perform a jar test can save you thousands of dollars in wasted product, equipment damage, and crop loss. Make it a standard practice for every new tank mix.

Remember: W-A-L-E-S

Water Soluble → Agitate → Liquids → Emulsifiables → Solubles/Surfactants → Fertilizers Last