According to Gardening Know How, chrysanthemums need full sun, well-draining soil and low-nitrogen fertilizer in order to blossom. When grown in part shade with too much nitrogen-rich soil and wet roots, mums fail to thrive.

How do I get my chrysanthemum to bloom?

Plant the mums in well-draining soil that receives full sun. Fertilize well to encourage blooms. If the mums produce spring blooms, pinch them back before late summer to encourage fall flowering. Before winter, cover plants with several inches of mulch or straw.

How long does it take a chrysanthemum to flower?

If you plan on growing chrysanthemums from seeds, you can expect it to take about four months for the plants to mature enough to produce flowers. You can start them indoors in seed trays in early spring, then move them into the garden after the last frost.