Key Points
Grow-in marks a transition period between the end of construction and the beginning of day-to-day maintenance.
Growing-in the turfgrass, whether warm- or cool-season, requires a very different maintenance regimen when compared to maintaining established turfgrass.
In addition to establishing the turfgrass, the period leading up to and including grow-in is critical for the superintendent to be hiring and training staff, procuring materials and equipment, and planning for the permanent maintenance and storage facilities.
There are many sustainable methods and procedures of turfgrass maintenance that the superintendent can begin to implement during grow-in, before less sustainable maintenance practices become entrenched. Also, this is a period of large capital outlay so there are many key equipment decisions to be made that will impact the long-term economic, environmental, and communal sustainability of the facility.
This is also the best time to establish a turf nursery on site.
The Sequence of Grassing
During the course of fine shaping, sod (which has ideally been grown in native soil) will have been installed around areas that are most prone to erosion, including:
Ring around greens and tees
Green slopes and tee slopes
Ring around bunkers
Steep slopes
Ring around catch basins and manholes
Major drainage paths
Lake and channel banks
Soil erosion and sediment control measures will also have been in place throughout construction but this will be an opportune time to ensure that they are all still in place and functional.
Seeding and sprigging will begin on the greens and tees. Greens, green surrounds, and tees are typically planted by hand or with a walk-behind spreader (whether seed, sod, or sprigs) to avoid the possibility of larger planting machinery damaging the final grades. The limits of planting should be out to the limits of the throw of the green and tee sprinklers because these areas will be frequently irrigated during grow-in and overthrow to areas not yet seeded is wasted water.
For cool season grasses, once the seed has been broadcast, it’s good practice to then mulch the planted area to prevent erosion, hold moisture, and help to keep the soil temperature within the optimal range while the seed is germinating (lower soil temperatures under the heat of the sun and holding warmth during the cool of the night). Plus, the mulch will make it easier to see what areas have been planted and what still needs to be done. Warm-season sprigs won’t require mulch.
Any areas that will be prone to erosion but weren’t sodded, plus larger areas that can be mechanically seeded or sprigged with larger machinery - such as maintained rough and fairways – are planted next with the outer, non-maintained rough planted last. By following this sequence (working outward from the greens and tees), areas that have been seeded or sprigged can be closed off to foot and machinery traffic without impacting access to areas that haven’t yet been planted.
In terms of access, cart paths are best for getting around during the planting phase, with the non-maintained rough as a last resort because any damage to the finish grading will have to be repaired.
Preparation for Grassing and Grow-In
As the time for planting approaches, the consulting agronomist and superintendent will be working hard behind the scenes to ensure that everything that will be needed for the critical grow-in period is in place prior to planting. Key tasks include hiring and training staff, setting up a permanent or, just as likely, temporary maintenance area, acquiring maintenance equipment, and stockpiling any materials (fertilizer, seed, topdressing, fuel, spare irrigation parts, spare machinery parts, extra drainage materials, back-up erosion control measures, etc.) that may be needed. Once the first seed has been planted, the superintendent and the maintenance staff are typically going to be working from dawn to dusk, 7-days a week, until the grass has established.
Staff – The superintendent’s grow-in team will likely include at least an assistant superintendent, an irrigation technician, a fertilizer/chemical application technician, and a mechanic. Depending on the size of the area of grow-in, eight to ten additional staff (machine operators and laborers) are going to be needed for the many tasks and challenges expected during the period. The superintendent will not only be responsible for hiring and training this staff, but will also be setting their priorities and work schedules, overseeing machinery maintenance, working with the irrigation technician to adjust the irrigation system during grow-in, staying on top of the budget, and most importantly, making sure that the grass is growing!
Maintenance Facilities – The consulting agronomist and/or superintendent have probably been thinking about the permanent maintenance facility since the early stages of the project (see Step 3: The Importance of a Consulting Agronomist). However, since it’s out of the public eye, the maintenance buildings are often the last to be built (after the golf course and the clubhouse). At the very least, the superintendent is going to need both indoor and outdoor areas during grow-in for storing materials such as fertilizer, seed, topdressing, maintenance equipment, and spare irrigation and drainage materials. The mechanic will need an area for machine maintenance in addition to areas where the machinery can be washed after use. The staff will need a place to have meetings, toilets, and wash rooms. The superintendent and assistant superintendent will need an office with online availability, telephone, and space for the irrigation central controller.
Below are some examples of maintenance yard and maintenance building layouts, in addition to an equipment wash-off area detail.
See here for some low-cost and environmentally friendly maintenance area ideas: https://www.gcmonline.com/course/environment/news/golf-course-wash-pad
Maintenance Equipment – Buying maintenance equipment for a newly built golf course is very capital-intensive. As a result, golf courses typically seek lease or lease-to-buy deals with equipment manufacturers to allow for more flexible financing terms. It’s a good idea to acquire all equipment prior to grow-in so there won’t be any disruption in the maintenance during this critical time. There is some equipment that is more critical to grow-in than the day-to-day operation but much of it will be useful both during and after turfgrass establishment. The following is a list of the most essential maintenance equipment that should be on-hand prior to planting:
Tractor with low ground pressure (LGP) tires and trailers
Light duty utility vehicles (e.g. Gator, Workman)
Heavy duty utility vehicles
Pedestrian greens mowers
Pedestrian tees mowers
Fairway cylinder mowers
Lightweight floating head rotary mower
Pedestrian rotary mowers
Fly mowers
Lightweight fairway mower
Pedestrian sprayer
Tractor mounted sprayer
Utility sprayer
Hydroseeder
Pedestrian fertilizer spreaders
Pedestrian topdresser
Tractor mounted topdresser
Utility vehicle topdresser
Strimmers
Pedestrian blowers
Mini-digger
Hand tools (e.g. rakes, shovels)
Various hoses and mobile sprinklers
Some Opportunities for Sustainability
Grow-in represents a major shift away from construction and towards the day-to-day maintenance of the golf course. This is also a time of heavy capital expenditure on equipment and facilities, in addition to labor. As such, there are many opportunities at this juncture for the golf course operation to “get off on the right foot” in terms of sustainability – ecologically, financially, and in building good will within the community.
Choosing hybrid or electric maintenance equipment rather than gasoline or diesel helps minimize: the cost of fuel, noise pollution, carbon pollution, the potential for hydraulic oil leaks, storage costs/safety/security for fuels. Hybrid and electric vehicles generally have higher purchase costs but lower operating/servicing costs than gasoline or diesel equivalents so it pays to calculate the ROI over the likely lifetime of the equipment, whether leasing or buying.
Hybrid and electric engines are more typically found in equipment with smaller power requirements such as greens mowers (ride-on and pedestrian) and light duty utility vehicles. However, hybrid technology is becoming more available for larger mowing units and advances in battery technology have been rapid, allowing for more power and longer run-times between charges. Therefore, more of the maintenance fleet can now be clean energy than was possible even a year or two ago.
It’s becoming more common to see solar panels on the maintenance and cart storage buildings to help charge electric vehicles – both golf carts and maintenance equipment. This can lead to big cost savings on the electric bill and, if the solar array is large enough, can even generate income in some markets by selling excess power back to the grid.
It can pay to perform a mowing efficiency analysis to determine the ideal mowing patterns around the golf course. This will help the staff to maximize the time that the machinery is cutting versus the overall time that it is being operated and also to maximize the percentage of the distance driven that the unit is cutting – potentially lowering fuel and labor costs, in addition to wear and tear on the equipment.
The equipment should always be maintained according to specifications so that it can perform at its best. Well maintained mowers with sharp blades will save fuel and improve the look and health of the turfgrass.
One technology that’s gaining traction in the marketplace and will soon become much more common is autonomous, GPS-guided mowers, topdressers, and sprayers, which will save on labor costs and will help to maximize efficiency – reducing fuel costs and equipment wear and tear.
See here for more information: https://eigca.org/news/EIGCA127461.ink
This is a concept mower from The Toro Company and is not currently in production
All maintenance facilities should have equipment wash-off areas that collect contaminated water (grass clippings, chemicals, hydrocarbons) for treatment and re-use or proper disposal (see Equipment Wash-Off Area Example above).
All “green waste” (grass clippings, leaves, wood chips, plant-based food waste, etc.) can be composted or placed in worm bins and, once broken down, can be used as bulk fill, mulch, for soil conditioning in amenity areas, or even for divot mix. This will remove a significant amount of material from the facility’s waste stream. It’s important to note that composting areas should either be within impermeable containers or be built on impermeable surfaces to contain leachate to avoid groundwater nutrient contamination.
Ideally, there should be recycling of all paper, plastic, glass, aluminum, and cardboard generated on or by the golf course. Bins must be widely available and clearly labeled. Perhaps more importantly, the ability to recycle products and the packaging they come in should be part of the purchasing decision. Members and staff must be educated on what is and isn’t recyclable and the benefits of keeping this material out of the landfill.
See here for more information about composting and recycling in an effort to become a “zero waste” golf course: https://www.usga.org/articles/2011/10/a-zero-waste-golf-course-is-it-possible-21474843749.html.
Even at a slightly higher unit cost, it will probably pay over the long-term to source equipment and materials locally, establishing sustainable supply chains and building goodwill with the community while also supporting the local economy.
Hiring and training staff from the local workforce can also engender support from the community – the more the local economy comes to depend upon your facility, the more goodwill it’s likely to enjoy.
Finally, during grow-in (and after) it will always be good practice to:
Control leaching, run-off, and erosion by irrigating only as needed.
Take care in the handling and application of chemicals – pesticides, fertilizers, fungicides – both to ensure worker safety and also to minimize misapplication or spillage.
Ideal Planting Conditions and Grow-In
Once the grass has been planted, the consulting agronomist and the superintendent will be anxiously monitoring the weather reports for the next 6 to 8 weeks and hoping for “ideal conditions” until the turf has established enough to be relatively safe from erosion and wash-outs.
What constitutes ideal conditions varies based on whether cool or warm season grasses are being used. In general, the four main factors that contribute to successful plant establishment are: soil moisture, nutrition, light, and temperature.
It is imperative during the establishment of turf that the soil surface remain moist so, for the first few weeks after planting, the irrigation will likely be needed for a short duration many times a day. The goal is to meet, but not exceed, the rate of evapotranspiration so there isn’t wasted water and excess runoff. Modern irrigation systems with moisture monitors will allow the superintendent to monitor soil moisture and apply water precisely to the needs of the establishing turf (see Step 10: The Design and Installation of the Irrigation System).
Nutrition during grow-in will be handled with regular applications of the appropriate fertilizers. Since a sand-based rootzone is especially prone to nutrient leaching, newly seeded turfgrass will need at least five times more nutrients than established turf to thrive. This will be accomplished with repeated light applications of fertilizer over the course of grow-in.
Topdressing is another maintenance practice that is highly recommended during grow-in. Frequent and heavy applications of sand will result in a firm, dry, and smooth playing surface. The sand used for topdressing must be physically consistent with the sand used in the rootzone.
Temperature and light are not within the consulting agronomist or superintendent’s control so it stands to reason that the best way to ensure ideal soil temperature and light is to plant the turfgrass at the right time of the year.
For cool season seed, the optimal soil temperature for germination is within the range of 70 to 75° F (21 to 24° C), but temperatures between 45 and 90° F (7 to 32° C) are within the acceptable range. Turfgrass will not germinate when the daytime temperature is regularly below 45° F (7° C) or when the nighttime temperature is regularly above 70° F (21° C). The time of year for these temperature ranges will vary based on location but, in the United States, this means that the ideal time to plant cool season seed is during the late summer and early fall, at least 45 days before the estimated date of the first frost. Late spring or summer is less than ideal because conditions in the seedbed will also be optimal for weeds, which will easily outcompete the not-yet-established seeds and young turf. In addition, the new plants are not likely to fare well with the heat stress, disease, and insects that are most prevalent during the summer months.
Warm season turfgrass sprigs are more mature than seed and have a much higher heat tolerance than cool season seedlings and, as a result, are better equipped to compete with summer weeds. Therefore, the ideal time to plant warm season turfgrass sprigs is early summer, after the spring weeds have already come up and been brought under control. The optimal soil temperate for the growth of warm season sprigs is above 70° F (21° C). If planting must be pushed to the early fall, the sprigs should be planted no later than 60 days before the estimated first frost. This will give the sprigs enough time to establish before winter dormancy.
For both warm and cool season turfgrasses, the soil surface must remain constantly wet for the first three to four weeks after planting. In addition, young plants that are establishing will need light applications of quick-release fertilizer multiple times during grow-in. Both of these practices are in contrast to the maintenance and care of established turf, which requires less frequent but longer duration irrigation and less frequent but heavier applications of slow-release fertilizers.
Erosion and Sediment Control
The biggest threats to a successful grow-in are erosion and wash-outs. Small wash-outs must be repaired immediately or they will rapidly deteriorate into larger wash-outs during the next rain or irrigation cycle.
The most efficient way to deal with washouts is to take action before they occur by identifying areas that have a high potential for erosion (e.g. steep slopes and areas of concentrated overland runoff) and proactively installing silt fences and other temporary erosion and sediment control features. Excess runoff from irrigation can be avoided by irrigating several times per day using a computer-controlled system that adjusts the run-time based on real-time atmospheric, soil moisture, and infiltration data.
Mowing
When the majority of the grass has grown to 2 inches (50 mm) and the ground is firm enough to support their weight, light mowers can be deployed for the first mowing of the new greens. Initially, the greens can be cut to 1 inch (25 mm) and gradually lowered to 1/2” (12.5 mm) for cool season grasses. Bermudagrass (warm season) greens should not be mowed at less than 3/8” (10 mm) before they are fully established.
Special care should be taken to ensure that the ground surface, which is likely still soft, is not dented by the maintenance equipment or foot traffic. At around the same time as the first mowing, the greens can also be lightly rolled two to three times in different directions to smooth the putting surfaces. After 6 to 8 weeks, the greens turf should be ready for lower cutting, gradually cutting down to the playing height (ranging from 0.1” to 3/16” (2.5 to 5 mm)).
The fairways can initially be maintained at twice the normal playing height, or around 1” (25 mm). At full maturity, cool season fairways will most likely be maintained between 3/8” to 1/2” (10 to 12.5 mm) with warm season fairways cut slightly higher, 3/8” to 5/8” (10 to 16 mm).
None of the maintained turfgrass should be allowed to grow higher than 2.5” (62.5 mm) before mowing. The frequency of mowing will depend on the growth rate of the grass but should be happening at least once per week following the first cutting.
From Grow-In to Regular Maintenance
As the cutting heights decrease and the turfgrass is maturing, grow-in regimens are gradually phased out and regular maintenance practices are introduced. Irrigation scheduling moves away from short-duration cycles many times daily to long-duration cycles once daily. Fertilizer application moves from light and quick release to less frequent but heavier applications of long-release nutrition. Mowing changes from once per week to at least five times per week on the greens, three times per week on the tees and green collars, and twice weekly on the fairways. Pesticides and herbicides are slowly introduced as needed.
Where turfgrass hasn’t established fully or adequately, spot-seeding or sodding and hand watering may be necessary. Erosion control measures are removed as the turfgrass establishes and the threat of wash-outs lessens.
Aeration and further topdressing of the greens should not be undertaken until at least 3/8” (1 cm) of thatch has developed. This will give the putting surfaces enough cushion to withstand foot and machine traffic and airborne golf shots.
Landscaping Installation
With the arrival of the following spring and warmer temperatures, the turfgrass should be close to fully established and nearly, if not fully, ready for regular play and maintenance. Where the ground is firm enough, smaller landscape planting of native and ornamental species can now happen, with final adjustments made to the irrigation system (including adding drip lines) to accommodate the new plantings.
The Turf Nursery
The purpose of the turf nursery is to provide sprigs and sod for both construction and maintenance of the golf course. Despite a higher initial capital expenditure, having a turf nursery on-site will ultimately lead to cost savings as the cost of transportation and middle-man mark-up to import turf will be largely eliminated. In addition, the quality of the turfgrass produced will be more uniform with the turfgrass being grown on the golf course since it will be grown in soil consistent with the rest of the golf course and maintained in the same way and using the same labor and materials.
At the same time that the golf course is being planted, nursery areas should be established for the turfgrasses used on the greens, tees, fairways, and roughs (which can be up to four turfgrass types). These will potentially require different maintenance regimens (mowing, irrigation, fertilizing, chemical applications, topdressing, etc.), just as with the corresponding turfgrass areas on the golf course. Furthermore, these areas should be built using the same rootzone materials and thicknesses as is found on the golf course.
The turf nursery will typically be graded so that it is nearly flat but with enough grade and drainage to ensure overland flow and collection should there be any runoff.
Contact Sustain Golf for More Information!
We would be happy to make recommendations or answer any questions that you might have about sustainable and accessible golf course design, construction, or maintenance. Visit www.SustainGolf.com or contact us at the following address for more information: Contact@SustainGolf.com.
The European Institute of Golf Course Architects (EIGCA), in partnership with the GEO Foundation, has developed a continuing professional development program for its members called Raising the Standard of Sustainable Golf Course Development, or RSSGCD. This is the industry’s only structured program in the world to specifically train golf course architects in sustainable golf course design, construction, and maintenance best practices. A Sustain Golf team member has attained Stage 3 of this rigorous program.
A Sustain Golf team member is also currently serving on the EIGCA’s Sustainability Committee and is a GEO Certified Accredited Sustainability Verifier.
We firmly believe that common sense sustainable design, construction, and maintenance practices are the keys to the long-term survival of the game of golf. We aspire to be on the leading edge of applying sustainability concepts to golf course design, construction, and maintenance.
We will spend every day for the duration of the project on-site and/or coordinating with all contractors, subcontractors and professional consultants to be sure that no opportunities are lost and that the best golf course for your property is realized.
Up Next:
Step 18 – Clean-Up & Punchlist
Sustain Golf is a collaborative group of friends who also happen to be qualified Golf Course Architects. We are also qualified and experienced as Civil Engineers, Vertical Architects, and Project Managers. We have the breadth and diversity of experience and knowledge to offer a full suite of golf course design and construction services, from first concept to opening day on your new or remodeled golf course.
References:
Hurdzan, Dr. Michael J. Golf Course Architecture: Design, Construction & Restoration. Chelsea, MI: Sleeping Bear Press, 1996.
Fry, Jack, Ph.D. A Low-Cost Wash Pad Solution. GCM online, April 2019. Retrieved from https://www.gcmonline.com/course/environment/news/golf-course-wash-pad
Gross, Patrick J. A ‘Zero Waste Golf Course: Is It Possible? USGA October 25, 2011. Retrieved from https://www.usga.org/articles/2011/10/a-zero-waste-golf-course-is-it-possible-21474843749.html
Peer Review:
Dr. Keith Duff, former UK government wildlife agency Chief Scientist, current Golf Environment Consultant
Jon Scott, President, Jon Scott Golf Consulting LLC; former Vice President of Agronomic Services, Nicklaus Design
Andrew Brown, Senior Sales Manager – Global Business Development and Relationships, The Toro Company