Installing your StarPro outdoor putting green in a backyard landscape needs a crushed stone base for drainage and to hold the contours you create (Sand does not hold its form it “walks down”.)
On a level site add a minimum of 2″ of sub base per square foot on top of your cleared leveled site. The green should lay 2″ above the surrounding soil (you can taper off the edges to 3/4″).
The SUB BASE is 3/8″ minus gravel screenings meaning your gravel supplier has passed gravel through a 3/8″ screen so only the 3/8 inch and smaller pieces pass through. This mix has small particles as well as gravel up to 3/8″ and every size in between.
You’ll need about 12 pounds of gravel per square foot of green/boarder. Do not use pea gravel or sand. If you can not find “3/8 minus” you can mix 3/8″ gravel with 1/4″ minus gravel screenings (very common). The type of stone does not matter as long as it is crushed (has sharp edges).
The base will compact well with a plate compacter but will not harden like concrete. This base will drain and hold it’s form for years. Many of our customers roll up the green every year to change contours and create a new green.