For every procedure or process there is right way to do it and a wrong way to do it. Using Nature Safe properly when core cultivating is a little different because there is really no wrong way to do it. No matter how you do it, you will get some good results when you use Nature Safe following core cultivation. However, you will get better results with some methods than with others.
The process I personally like and have seen the greatest amount of success with involves first core cultivating and then removing the cores from the turf surface. Next, apply either Nature Safe 8-3-5 or 5-6-6, depending upon soil type, at the rate of 1 lb. N per 1000 sq. ft. of turf area. Immediately apply the topdressing mix of choice on top of the fertilizer. As soon as it has had a few minutes of lying in the sun to dry, start the process of dragging the topdressing into the holes. Make sure that the dragging is done in circular patterns so that the majority of the topdressing material and fertilizer remains on the green and does not get dragged off into the surrounding areas.
After the topdressing has been properly worked into the holes and into the surface of the green, it should receive a light watering, followed by a drying period for the remainder of the day. The water will begin the breakdown of the fertilizer particles. They will first swell up slightly after they are irrigated and then crumble as they dry in the sun. That evening, the green should be well irrigated to finish the process. If possible, for the next two or three mowings, mow without baskets, when the turf is dry, to avoid picking up any of the topdressing material.
Some people like to apply the topdressing material first and then apply the Nature Safe on top of the topdressing. The problem with this method is a disproportionate amount of fertilizer gets dragged into the holes and not enough remains on the green surface area between the holes. This can result in differential greening and excessive growth in the immediate proximity of the holes. When the fertilizer is on top of the topdressing it is almost totally dragged into the holes, leaving very little to fertilize the areas between the holes. Of course, you want a good portion of the fertilizer to go into the holes, but not all of it. When the fertilizer is under the topdressing, a large portion of it does get into the holes, but there is enough remaining on the green surface to avoid any differential greening. Some superintendents are overly fastidious about working the topdressing into the green or tee surface. The use of some of the new topdressing power brooms can do the same thing. They are so efficient that they leave very little on the surface. Bear in mind, some material needs to remain on the surface when you are finished, and some of this material needs to be fertilizer.
You will benefit from the first process explained above because greens and tees will recover much more rapidly than normal and turf quality and rooting will be improved for months to come. The turf will go into the winter much healthier than otherwise possible and will green up earlier in the spring.