How to Build a Base for an Outdoor Putting Green
Whether your golf game is improving or still needs lots of work, you can benefit from an outdoor putting green. Neither the living room carpet nor the back yard lawn can possibly replace a real putting green for putting practice quality. Follow the instructions below to begin building your own putting green, starting with the base.
Step 1 – Locate and Prepare the Ground
First, you will need to choose the plot of ground you'll use for your putting green. Pick a place that will be raised above ground level, a place where drainage water is not likely to drip onto the green.
Next, prepare the ground. Make sure it is solid enough to put base material on it by tamping it with a plate compactor. Lay your weed barrier over the tamped ground. This will not only keep weeds from growing up, but will help keep crushed stone from sinking into the base soil.
Step 2 – Build a Border
You'll need to keep your base material from spreading beyond the outer edges of your putting green. The best way to do that is to install a border, which can be a retaining wall build of brick or concrete block. The border should be solid enough that it won't be pushed out by the base fill as you compact it. You most likely will not need to mortar the bricks or block. Their weight should hold the base material inside the border wall.
Step 3 - Build Your Base
In adding your base material, be sure it is distributed within the border very evenly. Move the material with a garden rake or a square mouth shovel until you're sure the surface is as flat and level as possible. You'll need a slight slope for drainage, so figure that in as you level the base material.
Step 4 - Build Your Drainage System
Your putting green must be engineered to drain rainwater, snow melt, or other water off the green. This will mean you'll need to drain any water off the top of the green, rather than planning for it to drain down through the base. Although water could drain downward through the base if you chose to make your green perfectly flat, this type of drainage would in time damage and weaken your base. For every ten feet your green surface extends, you'll need one inch drop in your slope.
Step 5 - Compact Your Sub Base Material
Don't assume that your base material will eventually settle and won't need to be compacted. If you allow it to settle by itself, it will settle unevenly and will leave a bumpy and uneven surface. You'll need to first wet the sub base material, then compact it with your plate compactor. When finished, you'll then be ready to add your soil base.