Sweet wooddruff

I enjoy this little ground cover and it is not invasive here. Here it blooms in late winter and spring. However, this past year I had few blooms. Should a plant, specifically sweet wooddruff, be fertilized now to make sure it blooms in late winter and spring?

We have Sweet Woodruff all over... It blooms regularly in our zone 6 garden- late spring early summer, and we are also at 6500 feet above sea level with heavy snow falls in the winter....
We fertilize only in the Spring to encourage growth and its spreading ability.

You can lightly fertilizer now, but do not over fertilize, as it will only produce green foliage and no blooms.

I'll probably just use bone meal because we are so low in phosphorous in our soil. That really makes a difference in bloom for roses and angel trumpets. I've just never tried bone meal on sweet woodruff.