Although reading the green correctly is essential, you can hole even more putts by judging the grain properly.
The grain is the direction in which the grass grows. In mild climates, the grass grows straight up, so the grain hardly affects your putt. However, the grass is mown up and down, pushing it in one direction and then the other. These stripes give the same effect as natural grain.
With the mown grain the grass looks pale and your ball travels more quickly.
Against the mown grain the grass looks darker and will slow a putt down.
Across mown stripes the ball will hit a mini-wall as it hits the join between the different sections and will tend to veer off line towards the direction of the mowers path.
A green with a strong grain looks dull and dark when you stand on one side, and shiny and light from the other. When it looks shiny and light, you are putting with the grain, and the ball runs very quickly. With the green looking dull and dark, a putt is against the grain and runs relatively slowly. Recognizing this and understanding what it does to the ball's path is as important as gauging the slope and line of putt.
Golf courses in warm climates usually have greens with either Bermuda or bent grass. These grasses which shoot up quickly in the sun also grow in specific directions.
The direction the grass grows depends on where the green is - If there a sea or a natural lake nearby, it is very likely that the grain leads toward it.
Alternatively, the grain may point where the prevailing wind is heading, or it could lead away from mountains or even lean toward the setting sun. Taking all these factors into account is vital if you are putting on grainy greens.
An uphill putt against the green is extra slow but the same putt with the grain may counteract the effect of the slope and make for a normal speed putt.
When the green slopes downward and the grain runs against the slope, the putt is almost straight.
If both the slope and the grain run in the same direction, the line of your putt becomes more acute and you must play for more break.
If the grain runs sideways across the line of putt, it has the same effect as a sideslope. Aim the putt to curve with the direction of the grain.
Breaking putts with the grain become more acute while breaking putts against the grain will cancel out some of the slope.
A hot sun drys out the grass very quickly. If the green is sunken, or has trees overhanging it, parts of it may remain in shadow for longer than others. This means that sections of the green can be either bone dry or damp.
Remember this when you assess your putt - damp grass can slow your putt down considerably while dryness means a fast putt and a more acute break.
Lesson 3: Putting on two tiers