Daylilies (Hemerocallis spp.) are hardy perennial plants with dense, fibrous root systems that help them compete with weeds. Their clumping growth habit and thick foliage can naturally suppress some weed growth by shading the soil. However, weeds can still emerge in gaps between plants or in poorly mulched areas. Understanding the growth cycle of daylilies—such as their active growth in spring and summer—helps in timing weed control measures effectively.
Mulching is one of the most effective ways to control weeds around daylilies. Organic mulches like wood chips, straw, or shredded leaves not only block sunlight from reaching weed seeds but also improve soil moisture and fertility as they decompose. Apply a 2–3 inch layer of mulch around the base of daylilies, ensuring it doesn’t touch the crowns to prevent rot. Inorganic mulches like landscape fabric can also be used, but they may hinder the natural spread of daylily roots.
Hand-pulling is a safe and targeted method for weed control, especially for annual weeds. Since daylilies have shallow roots, care must be taken to avoid disturbing their root system. Pull weeds when the soil is moist to ensure complete removal of roots. Perennial weeds like dandelions or bindweed may require repeated pulling or the use of a weeding tool to remove deep roots without damaging daylilies.
Pre-emergent herbicides can prevent weed seeds from germinating around daylilies. Products containing corn gluten meal or trifluralin are options, but they must be applied before weed seeds sprout—typically in early spring. Avoid herbicides that may harm daylilies, and always follow label instructions. Note that pre-emergents will not affect existing weeds, so combine this method with other strategies.
For existing weeds, selective post-emergent herbicides can be used cautiously. Grass-specific herbicides (e.g., fluazifop) target grassy weeds without harming daylilies. Broadleaf herbicides should be avoided unless applied precisely (e.g., with a brush) to avoid contact with daylily foliage. Always test herbicides on a small area first and apply on calm days to prevent drift.
Healthy daylilies outcompete weeds naturally. Ensure they receive adequate sunlight (6+ hours daily), well-draining soil, and proper spacing (18–24 inches apart) to reduce weed-friendly gaps. Fertilize moderately in early spring with a balanced fertilizer to encourage vigorous growth. Overcrowded daylilies should be divided every 3–5 years to maintain air circulation and reduce weed invasion.
Low-growing ground covers like creeping thyme or ajuga can serve as living mulch, suppressing weeds while complementing daylilies. Choose non-invasive species that won’t compete aggressively for nutrients. Plant ground covers after daylilies are established, and monitor their spread to prevent overcrowding.
Consistent garden maintenance is key to long-term weed control. Inspect daylily beds weekly during the growing season and address weeds promptly. Remove spent foliage and debris where weeds might take hold. Combining these practices ensures a weed-free environment while preserving the health and beauty of daylilies.
