Memorial Day is the unofficial start to summer, but for golfers in cooler climates, it also signals that our courses are finally starting to wake up. Yet on courses I play in the Northeast, the same thing happens each year: Just as we reach this peak season and the greens are starting to roll well, they are aerated.

The ensuing days are the most frustrating of the year. Surely there must be a reason why our golf course superintendents wait until the greens are in good shape to aerate, right?

That’s the question I asked Mike Dachowski, the superintendent at Shelter Harbor Golf Club, a an exclusive private club in Charlestown, Rhode Island, ranked on our latest America’s Second 100 Greatest Courses list. Under Dachowski’s leadership, the course is among the top-conditioned courses in New England, as judged by our 1,800-plus course-ranking panellists.

Golf Digest: Mike, many of the courses I play in Northeast start to roll really well by mid-May or so, but then all of a sudden they are aerated. Is that timing intentional?

Yes, the timing of aeration is very important. If you aerate before the grass wakes up and reaches an appropriate growth potential, then the grass isn’t going to heal. It might take weeks for aeration holes to fill in because the grass just isn’t growing.

That’s why we aerate a few weeks into the season and not right at the beginning. We have to wait for the grass to wake up and start growing in. That’s frustrating for a lot of golfers, to have us aerate the greens just as they get nice, but trust me, they are going to heal way faster than if we aerated earlier in the season.

You mention an interesting term: growth potential. What’s that all about?

Growth potential is how quickly the grass is able to grow given the temperature. In the middle of the summer, our growth potential in coastal Rhode Island is nearly 100 percent, but in the winter for months, that number is far lower. For example, in December through February, our growth potential at Shelter Harbor is zero. The grass is completely dormant.

What growth potential are you looking for to be able to aerate greens?

We like to have the growth potential reach 50 percent. That’s when we feel comfortable that the grass will recover after aeration. Where we are in Rhode Island, it takes a few months to reach that threshold—usually about mid-May. In April, the growth potential is only about 10 percent, so if we were to aerate then, then the grass wouldn’t grow back in very well.

Of course, it’s worth mentioning that growth potential varies across grass types and location. For courses south of us, they might hit that 50 percent growth potential in April. It’s all about knowing your climate and adjusting your schedules accordingly.


Shelter Harbor Golf Club in Charlestown, Rhode Island

So when do you aerate at Shelter Harbor?

We do our spring aeration the day after Memorial Day. The greens are already rolling pretty well by then, but we aerate to limit thatch and maintain turf health. Since the grass has already reached a high growth potential, you’d be amazed how quickly the greens grow back in. We aerate on a Tuesday and by the following weekend the greens are already starting to roll pretty well again.

When do you aerate at the end of the season?

We aerate again on the day after Labor Day. Just like in the spring, it’s essential to time it right. If you aerate too late in the fall, when the grass has stopped growing and the growth potential is low, then the greens won’t recover before the winter. That’s a disaster. On the coast in Rhode Island, our growth potential nosedives in October, so it’s key for us to aerify and have the greens grow back in before October hits.

For any golfers frustrated about aeration, I get it, but if we don’t do it, the greens will really suffer. For us to get the greens in the best shape for the longest time, we need to do it a few times a year.

Main Image: GLYN KIRK