Golf courses take great care to maintain the quality of their greens and fairways. An important part of that maintenance is filling the divots that golfers make when they hit shots on the course. Divots are spots where a chunk of grass and soil gets displaced when a golfer’s club hits the ground on a swing. If divots are not repaired properly, they can turn into unsightly bare spots or even small holes in the turf. So what exactly do golf courses use to fill divots and keep their playing surfaces in top condition? There are a few different materials that may be utilized.
One of the most common substances for filling divots on golf courses is sand. Greenskeepers will often have bottles or bags of fine sand set out near the first tee box and on par 3 tees for golfers to use to repair their divots. The sand helps fill in the indentations and provides a base for the grass to regrow on.
Sand used for divot filling is usually a very fine grade, similar to beach sand. This allows it to easily slip into the divots and crevices in the turf. Courser grades of sand may not work their way thoroughly into the nooks and crannies of a divot. The sand particles also don’t compact down and smother the grass like soil might. Air and water can still permeate through the sand base to get to the grass roots.
When filling a divot with sand, the key is to gently work the sand down into the hole without overly packing or compressing it. The divot hole should be left slightly mounded with sand to allow for settling. Then nature and watering will naturally compact the sand a bit over time as the grass grows back through.
Using sand to fill divots provides a number of benefits:
- Sand drains well and does not hold water like soil, helping avoid puddles or overly soggy areas.
- It provides a stable base to support grass regrowth.
- Sand allows air and water to still reach grass roots.
- It resists compaction and settling long term.
- Sand is relatively inexpensive compared to some other divot fill options.
The main downside to sand is that it isn’t quite as natural looking as soil or grass filler when initially filling a divot. However, as the grass starts to grow back through the sand, it quickly starts to blend in with the surrounding turf. Overall, sand is a simple and effective choice used on many courses.
Another material used to fill divots is topdressing mix or topdressing sand. Topdressing is a mixture of sand and organic matter that is regularly applied to turf surfaces as part of routine maintenance and upkeep. By volume, topdressing mixes are usually about 90% sand and 10% organic matter.
The organic matter in topdressing can consist of things like sphagnum peat moss, compost, or recycled ground up grass clippings. This organic content helps provide nutrients to stimulate grass growth and recovery in the divots. Some courses may even enhance their normal topdressing mix with extra nutrients or fertilizer when using it specifically for divot repair.
Topdressing is often a preferred divot fill material because it closely matches the existing composition of the green or fairway. It contains sand for drainage and stability just like the underlying rootzone of the original turf surface. The organic content mimics the organic layer in the soil profile.
Using straight topdressing means there is no abrupt transition between the divot fill and the surrounding turf. As the grass regrows from the edges back into the divot, everything blends together seamlessly.
Courses with extensive topdressing programs may have special topdressing carts or trucks that greenskeeping staff use to conveniently transport and apply topdressing sand right to areas needing divot repair. Some courses also offer bags or bottles of topdressing sand for golfers to carry to use for filling their own divots.
The main downside to topdressing for divots is the higher material cost compared to basic sand. However, the benefits often make it worth the extra expense for heavily used courses invested in providing premier playing conditions.
While plain sand or topdressing sands are most common, sometimes just ordinary soil is used to fill divots on golf courses. This may be more likely on courses with lower budgets that don’t want to invest in special sands. Or occasionally soil is used on holes where play is only expected to be minimal, such as on shorter par 3s.
The soil used is usually whatever the native soil type is for the course. For example, courses built on clay soils will use clay soil to fill divots. Courses on sandy loam soils will use the sandy loam. This makes the divot blend in with the area, but doesn’t always provide good growing conditions for the grass.
Soil can occasionally be compacted down too tightly in divots, restricting water and air penetration to the grass roots. Denser soils like clay can be particularly problematic for this. Soil also doesn’t drain water as freely as sand, which can lead to some sogginess in the repaired divot.
Occasionally a course may amend their native soil with some extra sand or compost when using it for divots to try to promote better growing conditions. But in general, plain soil is not the ideal choice for filling divots compared to sand-based options. It is, however, inexpensive and straightforward to use.
Some golf courses have adopted the strategy of collecting their green waste from mowing and tree/brush trimming and grinding it up to produce an organic material that can be used for filling divots. Green waste like grass clippings, leaves, small branches and other plant debris is diverted from landfills and turned into a divot fill supplement.
This ground up green waste adds organic matter to help enrich the divot fill and stimulate recovery of the grass. It may be mixed with sand or sandy topdressing materials to create the divot fill product. A ratio of 80% sand and 20% processed green waste is fairly typical. But this can be adjusted based on the needs of a specific course.
Using green waste as a component in divot fill allows the course to recycle debris already being generated through normal grounds maintenance. It takes waste that would otherwise be hauled away and gives it renewed purpose. This supports sustainability initiatives and can potentially reduce costs for divot fill materials.
The downside is the upfront investment required to purchase a green waste grinder and properly process and store the material. There is also labor involved in collecting and transporting green waste to the processing location on the course. So courses must weigh whether the long-term savings outweigh the startup costs for equipment. But overall using green waste in divot mix can be an eco-friendly practice.
For some high play golf courses, simply replacing the divots with sand or soil isn’t enough. The divots see so much play that grass struggles to recover fast enough before the next divot happens. This can lead to unsightly bald spots. In cases like this, artificial turf inserts may be used to fill divots.
Pre-cut pieces of artificial turf are carried by groundskeepers to rapidly fill divots and provide an instant green surface again. The fake grass isn’t meant to be a permanent fill. But rather it serves to protect the area until real grass can reestablish.
Once grass has grown back strongly at the edges and started encroaching on the artificial turf insert, it can be removed. At that point the divot has recovered enough that just sand or soil filling will be sufficient from that point on.
Artificial divot fills are mainly seen on courses that host elite professional tournaments or that have extremely high rounds played per year. They provide a way to keep even heavily used areas looking pristine for play and for TV broadcasts. But the cost of the synthetic turf inserts can be prohibitive for many courses.
An alternative technique involves using plugs of live grass “sod” to fill divots. To do this maintenance staff periodically extract small cylindrical plugs from healthy turf areas of the course using a plug cutter tool. These plugs are kept refrigerated until needed for divot repair.
When it comes time to fill a divot, the pre-cut sod plug is inserted into the hole. A mix of sand or topdressing is then used to fill around the plug and set it at the proper height. The live grass in the plug rapidly grows together with the surrounding grass to fill in the divot naturally.
This strategy doesn’t work for every course and every situation. There needs to be readily available areas where live sod plugs can be harvested from without damaging the source turf. And refrigeration equipment is needed to store and maintain the harvested plugs. Labor is also required to cut, transport and install the sod plugs in divots.
But under the right conditions, using live grass plugs can provide a seamless, natural looking divot repair that blends perfectly with the existing turf. This solution is seen more often on higher end golf courses invested in providing exceptional course quality.
Organic Soil Amendments
Sometimes other organic soil amendments are mixed into divot fill to supplement the nutrients and biology in the sand or soil used. A wide range of natural materials may be employed for this purpose:
- Compost – Adds beneficial organic matter and microbes.
- Peat moss – Increases organic content and water retention.
- Coconut coir – Supplies organic material and micronutrients.
- Worm castings – Introduces nutrients from worm excrement.
- Biochar – Provides mineral content and microbial habitat.
- Humic acid – Increases organic compounds to stimulate soil.
- Mycorrhizae – Adds symbiotic fungi to aid plant roots.
- Seaweed extracts – Supplies amino acids, vitamins and minerals.
These types of amendments work on the principle of enriching the divot fill media to better feed the turfgrass and soil biology that aids recovery. Even in small proportions, the right amendments can provide added benefits.
The downside is that exotic amendments can get expensive. Determining which options actually generate a measurable return can take research and experimentation. Cost-benefit analysis is important to determine if the boost in divot recovery is worth the added material expense. But judicious use of natural organic amendments can be a helpful tool.
Synthetic Turf Fertilizers
Another divot fill additive option is synthetic turf fertilizers. These are specially formulated fertilizers designed for use on golf greens and fairways. The nutrients in the fertilizer work to accelerate turfgrass regrowth and recovery.
Dry synthetic fertilizers may be directly mixed into the sand or soil used to fill divots. Or courses may use specialized sprayable liquid fertilizers applied right into the divot cavity before filling. The fertilizer is then watered in along with the divot fill material to receive the full benefit.
Some courses get very aggressive with divot fertilization, applying high nitrogen mixes to push fast grass regrowth. This needs to be done judiciously to avoid overfertilization. Moderate, controlled use of turf fertilizers in divot mix is often more prudent.
As with soil amendments, the economics need to be considered when adding expensive specialty fertilizers to divots. But the agronomic boost can justify it on courses where divot recovery is a chronic issue affecting course conditions and playability.
Considerations When Selecting Divot Fill
Golf course superintendents and greens committees must weigh a number of factors when selecting which materials to use for divot filling on their course:
– **Play Levels -** Courses with more rounds played overall or higher divot rates may need more advanced solutions like turf plugs or synthetic turf inserts. Simple sand may suffice on low-use municipal courses.
– **Drainage -** Proper drainage and drying of divots affects how quickly grass recovers. Sand is better for wet regions. Soil can work in drier climates.
– **Material Costs -** Specialized mixes and amendments can improve recovery but may be cost prohibitive. Budget dictates options for some courses.
– **Labor Factors -** Methods requiring more intensive labor like turf plugging may not be feasible for all operations. Simple sand or soil filling requires less worker time.
– **Aesthetic Priorities -** Some courses demand flawless divot appearance for events or reputation. Others are less concerned about temporary cosmetic issues.
– **Environmental Goals -** Using recycled green waste and organic amendments supports sustainability. This matters more to some courses than others.
There are arguments for and against all the different divot fill options. It comes down to selecting the right method for the specific course needs, budgets and operations. Most facilities choose two or three good material options to have on hand for different situations. Divot filling is just one important practice to support great course conditions. But it takes a thoughtful strategy to get it right.
While golfers want to think that grass will magically repair itself after their swing takes a divot, that isn’t the case. It actually takes concerted effort by groundskeepers to fill the hundreds or even thousands of divots that may accumulate on heavily played golf holes each week.
Sand and sand-based topdressing mixes are the most popular choices for divot repair. But soil, green waste, turf plugs and synthetic turf inserts may also be used depending on the needs of a course. Economics, convenience and course priorities all factor into which options a superintendent chooses.
Divots are essentially small wounds on living turfgrass plants. If treated properly, the plant will eventually heal itself through regrowth. But the right divot fill material hastens recovery and minimizes any scarring on the course. Beautiful playing surfaces don’t happen by accident. Conscientious divot filling is just one small but important practice greenkeepers use to maintain excellent golf conditions.