As long as you insist upon gardening, you might as well resign yourself to one of the cold, hard facts of life -- you will always have to contend with weeds. It’s a royal pain to remove even wimpy weeds from thick daylily foliage, but dollar weed is stubborn and downright ornery. Although it’s kind of cute with its scalloped edges, don’t let dollar weed fool you. This little stinker is a particularly tough, persistent, obnoxious pest with serious behavior issues. It stampedes through lawns, gardens and daylily beds via rhizomes, seeds and tubers. Keep an eye out for this miniature menace, and attack it persistently to retain the upper hand.
Apply pelletized corn gluten meal to the daylily bed in early spring. Spread 5 pounds evenly over 250 feet of gardening area. Water the material lightly into the topsoil. Corn gluten meal applications are effective for about five to six weeks. Use it in late February or early March in warm regions. If your area experiences long freezing winters, apply corn gluten meal in April or early May. The idea is to set it out just before spring dollar weed seeds begin to germinate. Follow the packaging instructions carefully.
Mulch the daylily bed with 2 to 3 inches of leaves, pine bark or pine needles. Mulching goes a long way toward controlling weed emergence.
Remove dollar weeds the moment you notice them. Use a hand trowel to dig down into the soil to retrieve the plant’s roots and rhizomes. Small pieces of rhizomes left in the soil regrow readily. Pick up pulled materials and dispose of them in the trash. Don’t add dollar weeds to the compost heap, where they’ll root quickly.
Cut the top half off an empty plastic 2-liter bottle. Discard the cap and the bottom of the bottle. Cover an individual dollar weed with the top of the bottle to protect nearby daylilies from harm. Pour vinegar through the spout slowly to wet all parts of the weed. Continue pouring to soak the soil well enough for the vinegar to seep down to the roots. Repeat daily until the dollar weed shows signs of distress. Vinegar is a strong, non-selective herbicide that damages any plant it touches, so take care that you don’t get any of it on the daylilies.
Evaluate your watering practices as dollar weed thrives best in wet conditions. Daylilies are somewhat drought tolerant and don’t require more than 1 inch of water weekly, including rainfall. Water slightly less than that as long as your daylilies continue to perform well.
Reapply corn gluten meal to the daylily bed in mid-August to treat late-arriving dollar weed seeds.