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Depending on where in the world you are playing your golf, the type of grass on the putting green could affect the roll and outcome of your putts. If you played golf in the United Kingdom then the grass on the greens are not very grainy so there will be no effect at all on the way your putt rolls.

Now if you where playing in the United States, there are a variety of different grasses used on the greens and you will need to account for the grain when you read your putts.

The grain is the way the grass grows and if the type of grass is grainy then you will be able to see which direction the grass points in. You will be able to identify whether your putt is into the grain or down the grain, and putts into or down the grain will affect your speed the most.

If your putt is down the grain then the speed that your ball will roll at will increase. It is important that you look at rolling your putt at a point that is shorter than the hole. This will account for the extra speed your down grain putt will have. If you dont take this into account, your ball will go racing past the hole.

If you have a putt that is into the grain, your ball will be running against the grass. This will create extra friction and slow the ball down. If you dont allow for this when assessing your putt, you will always leave it short of the hole. Make sure you pick out a point that is at least a couple of feet beyond the hole. This will help you get your speed right.

If your putt is across the grain then you will also need to adjust your speed as the ball will gather pace as it takes the break because it will then start to travel down grain.

Although the grain will have an effect on the amount of break your putt takes, it will also influence the speed of the roll, especially towards the end. This is because a putt will break to the lowest point and that will be running with the grain, so your ball will break more due to its continued roll from the extra speed.

Not only will you see the different speed your ball will travel but you will see a different roll too. The down grain putt will almost look like it is hugging the grass all the way through the putt, whereas the putt that is into the grain will start to jump and bounce a little as the friction into the point of the blades of grass kicks in.

This may be true for a putt that is down the grain but when your putt is into the grain, you need to hit it harder. You should try to imagine that the length of your putt is around four feet longer than the actual distance so that your ball will have the chance to get up to and at worst slightly past the hole.