When to Stop Fertilizing: Ornamental Grasses in Late Fall

Ornamental grasses are a popular choice for adding texture and movement to gardens. Proper care, including fertilization, helps them thrive. However, knowing when to stop fertilizing in late fall is crucial for their health and preparation for winter.

Understanding Ornamental Grasses and Fertilization

Ornamental grasses are hardy perennials that can tolerate a range of conditions. Fertilization provides essential nutrients that promote growth and vibrant foliage during the growing season. But as the season winds down, the timing of cessation becomes important.

Why Timing Matters

Applying fertilizer too late in the season can encourage new growth that is vulnerable to winter damage. Conversely, stopping too early might limit the plant’s ability to store energy for next year. Striking the right balance ensures healthy, resilient grasses come spring.

Signs of Late Fall

  • Temperatures consistently dropping below 50°F (10°C)
  • Foliage beginning to brown or die back
  • Reduced growth activity
  • Longer nights and shorter days

Best Practices for Fertilizing

Experts recommend stopping fertilization about six weeks before the first expected hard freeze. This allows the grasses to enter dormancy naturally and prepare for winter conditions.

Timing Guidelines

  • In most regions, cease fertilizing by late October or early November.
  • Adjust based on local climate and first frost dates.
  • For areas with mild winters, a light fertilization may be acceptable until late fall.

Additional Care Tips

Besides timing, consider these tips to care for ornamental grasses in late fall:

  • Remove dead or damaged foliage to prevent disease.
  • Cut back the grasses to about 4-6 inches above ground after the first hard frost if desired.
  • Apply a layer of mulch to insulate the roots during winter.

Summary

Stopping fertilization in late fall is key to ensuring ornamental grasses are healthy and prepared for winter dormancy. Pay attention to local climate cues and follow recommended timing guidelines to support their long-term vitality.