Primo Maxx Plant Growth Regulator - 4 oz

  • $54.99
  • $45.99

Want to mow 50% less while getting greener and thicker grass at the same time?  Then it's time to add Primo Maxx plant growth regulator to your lawn care program. It's safe and easy to apply.  A single application slows grass growth for up to 4 weeks.

  • Reduces mowing and edging by up to 50%
  • Promotes lateral growth for a thicker, denser lawn
  • Enhances heat, drought, and disease resistance
  • Stimulates root growth for healthier grass

Primo Maxx works on all grass types and is safe for commercial and residential turfgrass. This plant growth regulator is safe for the following grass types:

Warm Season

  • Bermudagrass (hybrid and common)
  • Buffalograss
  • Bahiagrass
  • Carpetgrass
  • Centipedegrass
  • Kikuyugrass
  • Seashore Paspalum
  • St. Augustine
  • Zoysiagrass

Cool Season

  • Bentgrass
  • Fescue (red, tall, turf types)
  • Kentucky Bluegrass
  • Blends (Bentgrass/Poa Annua, KBG,Ryegrass,Poa Annua)
  • Ryegrass (annual and perennial

     The active ingredient in Primo Maxx is trinexapac-ethyl. To learn more about plant growth regulator and tips on getting the best result, take a look at this video. 

    Item weight: 4 oz.

    Active Ingredient: Trinexapac-ethyl 11.3%

    Primo Maxx can be used on all grass types, such as the following:

    Cool Season Lawns - Kentucky Bluegrass, Turf Type Tall Fescue (all fescues), Ryegrass

    Warm Season Lawns - Bermuda, St Augustine, Zoysia, Centipede, Bahia

    We recommend applying Primo Maxx through foliar spray. It can applied alone or tank mixed with other products. We have tested Primo Maxx with our liquid fertilizers and biostimulants and observed no adverse interactions. Confirm compatibility with other products using a jar test.

    Pro Tip: Improve the performance of Primo by mixing a small amount of liquid fertilizer along with it. Release 9-0-1C or Golf Course Lawn 20-2-3 are excellent choices. Use a rate of 3 - 6 oz. per 1000 sq. ft. for these fertilizers.

    Label: Primo Maxx PGR Product Label

    SDS: Primo Maxx Safety Data Sheet

    Application: Battery-powered 4 gallon sprayer with  TeeJet foliar spray tip recommended.

    When to Apply: Whenever your grass is actively growing. Top dressing and aeration does not reduce product effectiveness.

    Product is safe for warm and cool season lawns.

    Coverage: 7,000 to 16,000 square feet depending on grass type and application rate.

    Primo Maxx Application rates:

    Cool Season Grass Application Rates

    Primo Maxx Cool Season Application Rate

    Warm Season Grass Application Rates

    Primo Maxx Warm Season Application Rate

    Does Primo Maxx need to be watered in?

    • No. Primo Maxx works via foliar uptake. Simply spray your lawn and allow it to dry.

    How long should I wait before resuming mowing?

    • If it is your initial application for Primo Maxx, we recommend waiting 2 days. Mowing can be resumed the following day for subsequent applications. For additional guideance on using Primo Maxx, see this article.

    Can I apply granular fertilizer or Essential-G on the same day as Primo Maxx?

    • Yes. We recommend that granular fertilizer and Essential-G be applied before Primo Maxx.

    Can I apply other liquids and Primo Maxx on the same day?


    Shipping: United States Only.

    Currently NOT shipping to: (AK,HI). For AZ, CA, CO, WA, just a small shipping charge of $3.00 will be applied.

    We can not ship to PO Boxes

    Typically delivered in 4 - 7 business days.

    Cancellations | Returns | Exchanges: All sales are final, no cancellations, returns, or exchanges