Can you add a hole to an artificial putting green after it is installed?


Putting Green Help / Monday, August 27th, 2018

After playing my green for a while, I noticed some things that were hard to see on just looking at the green design on paper.  One of those things was my green could really use another hole, which got me wondering:

Can you add a hole to an artificial putting green after it is installed? Yes, you can add another hole to your synthetic putting green after installation.  The process involves the following steps

  • Vacuuming out the infill
  • Accessing the base under the turf
  • Excavating the base to make space for the new cup.
  • Cementing the cup into the base
  • Replacing the turf
  • Cutting the turf to expose the new cup
  • Adding back the infill
  • Brushing and rolling the green

The method below describes the steps to add a hole in synthetic turf without having to remove and replace the entire green.   To start out, I would rank this project as difficult and point out there is a risk of damaging your green by following this process.  It is best to seek out professional help if you are punching above your weight in this project.

Decide the new location of your hole.  Don’t take this decision lightly as you will see it is hard to remove the hole once it is in.  Once you have the right hole location.

Vacuum Out the Infill

Vacuum out the infill around where you will be adding the new hole.  Infill is the material (usually sand) that holds down your synthetic green and fills in between the synthetic fibers to make them stand up like blades of natural grass. You will want to vacuum out a large area to make the steps to come easier.

Accessing the Base Under the Turf

If your hole is near the edge of the turf, you may be able to just vacuum to the edge, unpin the turf and roll it back to where the whole will be.  If you want to place your new hole in the middle of the turf and rolling up the turf from the edge isn’t an option, you will need to cut a slit in your turf.

You will want to cut this slit into the weave that makes up the base of the turf fabric without cutting the turf fibers that are sticking up.  You will be patching this slit back together later in this process so take extra care here.  It is important to make the cut with the weave of your green.  If you were to flip the turf over you would see the weave on the back has a grid pattern.  Think about this when cutting a slit in the turf, you will want to cut along the grid pattern not diagonally across it.  The goal is to make this slit long enough so you have enough room to do the remaining steps of excavating the base, inserting and cementing in the new cup.  The goal of this cut is not to cut a circle to place the hole in.  That will be done later as a separate cut once this slit has been repaired.

Excavating the Base to Make Space for the New Cup

Now that you have access to the base, either through the slit you cut or through rolling the turf back from the edge, you will want to dig a hole in your base that is 2 inches wider than the cup on all sides and 1 inch deeper.   This will give you room to add concrete around your base to anchor the cup from tipping or moving once you are done.  Keep in mind the base was compacted and is likely very hard to dig into.  If you can’t penetrate the base you could trying using a tile chisel like this one.

Cementing the Cup into the Base

Hold the cup in the hole and fill around the cup with concrete.  You will want the concrete mix to be a little stiffer than milk shake consistency, so it fills in the hole around the cup when you pour it in and jiggle the cup.   Use a trowel to smooth out the concrete and leave the cup level with the base fill material.  You should smooth and feather the concrete out around the cup 12-18 inches so you do not have any lumps or ridges leading up to the cup.  You don’t need to add any cement to the bottom of the hole when you put in the cup.  A quick tip-coat the cup with Vaseline or wd-40 before adding the concrete.  Then as the concrete dries twist the cup in the whole every few minutes to allow it to move freely.  This way when the concrete dries you can still remove the cup.  This can be great if you need to raise or lower the cup at a later time.  You will want your cup just below the green turf level when you are finished.

Replacing the Turf 

If you worked by rolling the green back to add the new hole you can simply lay the green back over the whole and pin it back down.  If you lost your pins you can find more here.   If you had to cut a slit in your green to access the location to put in the new hole now is the time to repair that slit.

To repair the slit you will need to line up the two sides of the slit to check for fit.  Once everything is in the right spot.  Use an artificial grass tape like this one to get the sides of the slit to hold back together.  To do this pull the turf back and place the tape under the slit, with the white backing strip up.  Keep the white tape backer on at this point so the tape doesn’t stick to everything.  Make sure the line up the center of the slit to the center of the tape.  Start by removing one side of the tap white backing strip slowly as you progress down the tape removing the white backing strip press the turf from one side of the slit down onto the now exposed sticky side of the tape.  Make sure you are lining up the edge of the slit with the center of the tape.  When you have finished one side repeat the process on the other side, slowly removing the white tape backer as you progressively move down the slit pressing the turf into the sticky side of the tape.  With this second side make sure you are lining the two turf edges up tight with no gaps.

Cutting the Turf to Expose the New Cup

Cut in the turf around the cup using the inside edge of the cup as your guide.   This can be done with a box cutter.

Adding Back the Infill

Replace the infill material you vacuumed out at the beginning of the process.  Match the sand that is used on the rest of your green.  If you can reuse the sand out of your vacuum that can be the most cost effective.  You don’t want to use just any sand.  It is important to have a fine silica sand with round grain, here is an example.

Brushing and Rolling the Green

Brush your green to stand up your green fibers and get consistency in your infill.  To do this brush against the grain to stand up the fibers of the turf and allow the sand to settle and support the turf fibers in a vertical position.  Follow that up by brushing the green from every direction to make sure you don’t have a distinctive grain pattern in the green that would effect your balls line of travel.

Lastly, you can roll your green to bend the top of the fibers and increase green speed.   Big yard rollers like this one work well as you can vary the amount of water you put into the drum to control the weight of the roller.  For more information see that article I wrote on speeding up your synthetic putting green.