Fall golf prep: Traditional overseed, liquid overseed or both

Jul 28, 2017
It's never too early to plan. What you do this fall and winter may be less expensive to choose now. There are several considerations to review when choosing whether to leave dormant turf as-is or whether to choose between traditional overseed, liquid overseed or both. [caption id="attachment_287" align="aligncenter" width="600"]Before and after pictures reveal Endurant liquid overseed transforms dormant turfgrass into lively, healthy looking green grass Endurant eco-friendly turf colorant applied at Hillwood Country Club provides a vibrant turfgrass transformation during full winter dormancy. Endurant also provides a boost in color when low temperatures cause intermittent browning.[/caption] There are a few superintendents who still use the old practice of overseeding warm season grass with perennial rye grass seed during fall and winter dormancy. Traditional overseed costs more than colorants or hybrid overseed and often has a costly environmental impact in terms of water, fertilizer and chemicals. Also, traditional overseed causes less than desirable ramifications on the turf the other months of the year. Nonetheless, there may be a time to overseed in the traditional manner of putting grass seed on top of grass that is going dormant in the cooler weather. There are also many times that "liquid overseed," or applying a colorant is best. And yet, there is another option, "hybrid overseed," or doing a bit of both, that is becoming popular in the western U.S..

What is liquid overseed?

There was a time, prior to 2010, when using colorants on dormant turfgrass was a new practice. Early on, there were few if any golf course superintendents seeking or using an alternative to the practice of overseeding warm seasons grasses with perennial rye grass seed. When the practice was new, courses, such as Pinehurst #2, may not have wanted to give away their secret to success, adding colorant when most golf courses were losing color and sowing costly seeds. As it became known throughout 2010 and 2011 that painting, pigment and colorant applications were a less expensive practice than overseeding, some professionals didn't want anyone to think they were using Endurant turf colorants to save money. These golf courses were offering a high end product, not trying to be cheap. So, perhaps, in part because painting grass sounded weird and it was a new secret sauce replacing an old tradition, many professionals called the practice of paint turf "liquid overseed." Whatever the reason, it has caught on throughout most of the country and certainly the south.

Will golf course superintendents choose traditional overseed or liquid overseed this fall and winter?

That may very well be a trick question. There is another option that is becoming very popular, particularly among golf courses superintendents in the western U.S., said Jenniver Seevers of Geoponics.

What is hybrid overseed?

"We're seeing these golf course superintendents out West choosing to do both. They used to heavily overseed, which means they were using tons of water, fertilizer, everything. Now, they're doing what we're calling a hybrid overseeding," said Seevers. Golf course superintendents are cutting down on the seed, water, fertilizer and other chemicals and using at least some colorant. Hybrid overseed is a little bit of both-- overseed and liquid overseed. Eastern and southern golf courses, on the other hand, have almost all done away with overseed and are strictly using colorants instead. Nonetheless, for TV or for tournaments, there are courses choosing the hybrid overseed for the ultimate in aesthetics, agronomics and playability. This hybrid option can also be the middle road environmentally in terms of water and chemical usage by reducing some overseed, but without doing away with it entirely.

Does grass have to be green?

Overseeding is done when a golf course's Bermuda grass in the fairways, tees boxes and greens is about to go into its brown dormant stage. Each autumn, as temperatures drop below 60 to 70 degrees, many Bermudagrass golf courses go brown and are overseeded with ryegrass. The grass seed is spread on top of the existing grass to promote new growth and to swap out seasonal turfs, replacing one type of grass with another. This causes an awkward transition between seasons aesthetically, agronomically and in terms of playability. The course loses income potential as it has to close for the overseed process. Liquid overseed on the other hand does not require days of a full course closure. Overseeding, or its alternative, is needed on golf courses to attract golfers in the winter and spring. Golfers want to see green grass. Studies all conclude that golfers want green grass. This is something most golf course superintendents do not need to learn via deep research. Golfers tell them. Bermuda grass or other warm season grasses will go off color if not totally brown as cooler weather approaches. Don't just take our word for the green grass desire. Director of Agronomy Shawn Emerson of Desert Mountain Club in Scottsdale, Ariz. has said: Golf is green. People want green grass. They don't want brown grass. "We've found Endurant is the best way to accomplish that to be TV ready and environmentally conscious," Emerson has said. Prior to 2010, it was traditional each fall for golf courses in warmer climates to overseed bermudagrass, which goes dormant in the winter, with ryegrass. Dr. Leah Brilman, director of research and technical services at the Seed Research of Oregon has explained why:
If you don't have green grass and the guy down the road has green grass, you may lose golf dollars. It's all about revenue."

Why choose liquid overseed?

Practices of overseeding bermudagrasses with perennial ryegrass and Poa trivialis, in some cases, is mostly a practice of the past due to expense and environmental awareness. In areas such as Florida ,where golf is a big industry and big draw for snowbirds, many golf courses used to overseed everything. They went "wall-to-wall" for six months of the year because those were the months that got the most play. However, the cost could be avoided. Now, few golf course superintendents overseed and once they try liquid overseed once, they don't tend to go back. As a Florida golf course superintendent told Golfdom, it cost $40,000 for seed. Add on seed care, it costs $100,000 with fertilizer, herbicides, fuel costs and labor to overseed a 90-acre course. The golf course saved money and weed control using "liquid overseed," which is a term used for paints, pigments or colorants. He saved about 1/3 of the cost and avoided an ugly and costly spring transition.

Traditional overseed challenges and drawbacks:

  • Weak areas and recovery challenges during transition back to bermuda the following summer
  • Overseed feeds namatodes during the cooler months
  • It is labor intensive
  • Overseeding costs more in everything: water, fertilizer, labor, equipment hours, chemicals and money. (Source: Golf Course Industry Magazine)
  • Can take away from ability to perform other maintenance projects
  • Requires more fertilization, coming at not only a financial cost, but also damaging soil quality and likely harming water quality nearby
  • Overseeding generally causes the course to close for an extended period, causing lost revenue
All those challenges above could be avoided by using liquid overseed instead of traditional overseed. Overseed benefits reported by some superintendents:
  • Looks great in the spring
  • May be more durable to high traffic

Colorant benefits:

  • Can provide great looking turf in each season with consistent color
  • Stronger bermuda grass in summer without winter overseeding
  • Weed control is easier
  • Costs less than the practice of overseeding
  • Reduces fertilizer usage
  • Minimizes over-watering
  • Reduces herbicide usage
  • Lowers demands and usage of many chemicals
  • Allows for other winter maintenance projects
  • Less labor intensive
  • Cuts fuel usage and costs
  • Requires less equipment wear and tear
  • Can provide better playing surface with dry, faster surface
  • Improves aesthetics with consistent color
  • Can add high contrast for targets if some of course area is left dormant
  • Gets courses TV ready and HDTV quality

Expert Tip:

When grass is dormant, whether painted or not, it's important to minimize excessive or unnecessary wear when possible. It's not because the paint will wear off but because grass that is not growing will not grow back when broken off by wear. Thus, sticking to cart paths becomes a particularly important winter rule for grass health.