I know an employer in my area (not lawn services) who has ups/downs seasonally, similar to lawn services. He has 3-4 people working for him.
Several years ago, he laid off a couple of them for a few months (maybe three?). They collected unemployment. His rate for the unemployment insurance went up significantly the next year. He quickly learned that it was more economical for him to find some little work for them during the off-season, or not have them report at all, but yet continue to pay them. The unemployment insurance rates rose to a level where he could not afford to lay them off.
That is just one instance, and may not be typical. You may or may not know what your rates will be for the next year, if these two folks draw off the insurance, until you get your bill. Your accountant may be able to provide other examples. But, as a previous poster said, your rates will likely go up. The question is how much?