Leucanthemum Cream Puff perennials are moderate feeders. We recommend applying fertilizer in the spring- so your plant has time to soak up the nutrients it needs for a healthy and successful growing season. You can use any liquid fertilizer at a rate of 50-100 ppm nitrate or a controlled-release fertilizer at a rate similar to 1-1.5 pounds of nitrogen per yard of growing medium. Do not fertilize this perennial in the winter; doing so could overfertilize them and cause their next growing season to not do so well.