Prodiamine Rates per 1,000 Sq Ft (Dosing Chart)
There is no single safe prodiamine dose for every lawn. Use the rate on the current label for your exact product, turf, target weed, and application timing. To convert a dry-product label rate from pounds per acre to ounces per 1,000 square feet, multiply by 0.367. Treat the examples below as conversions, not recommendations.
Prodiamine is a pre-emergent herbicide: it helps prevent certain weeds from establishing, but it does not replace a product label’s directions. The label sets where and how a product may be used, including its rate, timing, watering instructions, and annual limit.
Getting the math right can help you avoid both poor coverage and overapplication. I start with the product label and the measured area, then check the equipment and application plan before treating any turf.
How to find the right prodiamine rate
The correct rate is the rate printed on the label for your specific product and intended use. Formulation, turf type, target weed, timing, and split-application rules can all affect the permitted dose. An online chart is useful only if it matches those details and the current label.
Check the exact product label
Look for the product name and formulation, then find the directions for your site and turf. Confirm these details before measuring:
- Whether the product is granular or liquid
- Whether your turf species and site are listed
- Which target weeds are covered
- The permitted application window
- Whether the lawn’s establishment stage is allowed
- Any watering-in directions
- The maximum amount allowed per application and per year
- Personal protective equipment (PPE), cleanup, and replanting restrictions
A 65% prodiamine product contains 65% active ingredient by product mass. That percentage does not tell you how much product to apply. The product-specific label rate does.
Do not copy a rate from another brand, formulation, turf type, or website unless it matches the current label for your exact product and use. Do not apply to newly seeded, sprigged, or otherwise restricted turf unless the label expressly allows it.
Why a universal dose chart can mislead
Rates differ because labels may allow different amounts for different weeds, grasses, seasons, or application schedules. Some labels may also set limits for a single application and for the full year. A rate that is permitted in one situation may be too high, too low, or prohibited in another.
Treat any chart that lacks the product name and label context as a math reference only. The label is the authority for whether a rate is allowed.
Convert the label rate to 1,000 square feet
A rate conversion changes the label’s units to match the area you plan to treat. It does not change the label rate or decide whether that rate is suitable. First identify the product amount per acre on the label, then multiply by the area conversion factor.
One acre contains 43,560 square feet. So 1,000 square feet is 0.0229568 acre. For a dry product labeled in pounds per acre, use:
Label rate in lb per acre × 0.0229568 = lb of product per 1,000 sq ft
To express that answer in ounces, multiply pounds by 16. For quicker conversion, multiply the label rate in pounds per acre by 0.367 to get ounces of product per 1,000 square feet.
Dry-product conversion examples
These examples show the arithmetic only. They are not recommended application rates. Use a rate only if the exact label permits it for your turf, site, weed, and timing.
| Label rate, dry product per acre | Calculation | Equivalent product per 1,000 sq ft |
|---|---|---|
| 0.5 lb/acre | 0.5 × 0.367 | 0.183 oz |
| 1.0 lb/acre | 1.0 × 0.367 | 0.367 oz |
| 1.5 lb/acre | 1.5 × 0.367 | 0.551 oz |
These are ounces of product by weight, not fluid ounces. A kitchen volume measure cannot reliably replace a scale for a product labeled by weight.
Liquid-product conversion
For a liquid product, multiply the label’s product volume per acre by 0.0229568 to find the equivalent volume per 1,000 square feet. Keep the units used by the label. Do not infer fluid ounces from product weight or use a dry-product conversion for a liquid formulation.
If the label gives a rate in another unit or basis, follow its directions rather than forcing the rate into this formula. When the rate or units are unclear, contact the manufacturer or a local extension service before applying.
Calculate the amount for your lawn
The treatment area is the turf you will actually spray or spread, not the whole property. Measure it first, then apply the converted rate to that area. A careful area estimate helps prevent overlaps and reduces the chance of exceeding the label rate.
For a dry label rate expressed per acre:
- Measure the treatment area in square feet.
- Divide the area by 1,000 to find the number of 1,000-square-foot units.
- Multiply that number by the label rate per 1,000 square feet.
- Weigh or measure the total product using the label’s stated units.
- Check the total against per-application and annual limits.
Worked example: Suppose a label permits a dry-product rate of 1.0 lb per acre for your specific use. The conversion is 1.0 × 0.367 = 0.367 oz per 1,000 square feet. For 5,000 square feet, multiply 0.367 by five: the converted amount is 1.835 oz of product. This example demonstrates the math only; verify that the rate is allowed by your label before use.
For an irregular lawn, split the area into simple shapes, calculate each one, and add the results. Do not count beds, paths, or other untreated areas as turf. If the product label or local rules require a different method, follow those directions.
Calibrated application and site management
Calibration means checking that your spreader or sprayer delivers the intended amount over a measured area. A correct calculation can still lead to an incorrect application if the equipment releases too much, too little, or unevenly. Use equipment suited to the product and the label.
Match the equipment to the formulation
Use a calibrated broadcast spreader for a labeled granular product, or a calibrated sprayer for a labeled liquid product. Do not convert between formulations or substitute a generic spreader setting for a product label’s directions.
I use a measured test area before treating a full lawn. Divide a large site into sections you can track, and follow the product directions for application volume and equipment settings. Spreader settings vary by equipment and product; do not assume one setting will work for every setup.
Apply evenly and stay within limits
Apply only under conditions allowed by the label. Move at a steady pace and plan the route to limit skips and overlap. Overlapping passes can raise the dose above the label rate, especially around turns, narrow strips, and edges.
- Keep the product on the intended treatment area.
- Avoid drift or spread onto non-target areas.
- Water in only if and as the label directs.
- Follow the label’s weather, timing, and site restrictions.
- Stop if the area or product amount no longer matches your calculation.
Overapplication can injure turf and may leave residues that restrict reseeding or other planting. It can also exceed the label’s annual maximum or split-application limit. Recalculate for the actual area rather than trying to correct a mistake by guessing.
Worked application scenarios
These scenarios show how to use the conversion and planning steps. They are examples, not reports of a specific product or application. In each case, the actual rate must come from the current label for the product and site.
A measured 2,000-square-foot lawn
If the permitted label rate converts to 0.367 oz per 1,000 square feet, multiply by two. The calculated amount is 0.734 oz for 2,000 square feet. Before applying, confirm the label allows that rate and check that the equipment can distribute the amount evenly over the measured area.
A larger lawn with separate sections
For a 10,000-square-foot treatment area, mark out ten 1,000-square-foot sections. At a label-permitted conversion of 0.367 oz per 1,000 square feet, the total calculated amount is 3.67 oz. Tracking sections makes it easier to apply uniformly and spot a missed or repeated pass.
A liquid product labeled per acre
If the label states a liquid product volume per acre, multiply that volume by 0.0229568 to get the volume per 1,000 square feet. Multiply again by the number of 1,000-square-foot units in your treatment area. Keep the label’s units throughout; do not substitute a dry-product rate or estimate volume from product weight.
Cleanup, records, storage, and reseeding
Good records help you track what was applied and avoid exceeding annual limits. Cleanup and storage also matter: follow the product label for equipment care, personal hygiene, and safe storage, rather than relying on general advice that may not fit the formulation.
Record the product name, label rate, date, treated area, total amount used, and any split application. After treatment, clean equipment as directed by the label, wash hands and exposed skin, and store the product in its original container as instructed.
Check the label before reseeding or planting. Prodiamine residues may restrict when certain grasses or plants can be established, and those limits can vary by product and use. Do not assume that a general reseeding interval applies to your product.
Frequently asked questions
How much prodiamine do I use per 1,000 square feet?
Use the rate on your exact product label. If a dry-product label rate is stated in pounds per acre, multiply by 0.367 to convert to ounces per 1,000 square feet. Confirm the rate is permitted for your turf and use.
Is there one standard prodiamine rate?
No. Permitted rates vary by product, formulation, turf, target weed, timing, and application limits. A general chart cannot replace the current label.
How do I convert pounds per acre to ounces per 1,000 square feet?
Multiply pounds per acre by 0.367. This converts product weight only. It does not confirm that the rate is allowed for your specific use.
Can I use a rate from another brand?
Not unless it matches the current label for your exact product, formulation, site, turf, and target weed. Similar active ingredient percentages do not make products interchangeable.
Does 65% prodiamine mean I apply less product?
The percentage describes the share of active ingredient by product mass. It does not set the application rate. Follow the product label.
Can I use the dry-product chart for liquid prodiamine?
No. For liquid products, convert the label’s volume per acre using 0.0229568. Keep the label’s units and do not infer liquid volume from product weight.
What if I apply a split treatment?
Follow the label’s split-application directions and limits. Add all applications when checking the annual maximum; do not assume each split can use the full single-application rate.
Can I apply prodiamine to newly seeded turf?
Only if the product label expressly permits that use and establishment stage. Check the label’s restrictions before applying.
Should I water the product in?
Water it in only when and as the label directs. The instructions can differ by product and use.
What if I do not know the exact area?
Measure the treatment area before calculating the amount. Applying based on a rough guess can cause skips or overapplication.
(This article was written by one of our staff writers, Victor Dempsey. Visit our Meet the Team page.)
