What Is Making My Liriope Unhealthy?

Are the plants turning yellow?

Are the leaf tips brown?

Are the leaves scarred?

Are the leaves covered with small bumps?

Do the leaves have reddish-brown spots along their margins and tips?

Blue lily-turf plants or Liriope caught by a late spring frost suffer leaf discoloration, and they are slow to recover. Cover your plants with mulch, such as straw or leaf mold. Remove once the danger of frost has passed.

If planted in soil that is too wet or loaded with salts, leaf tips of Blue lily-turf turn brown. Improve drainage by adding lots of organic matter, replant in raised beds, or transplant to a more fertile site.

Although Blue lily-turf plants are virtually problem-free, slugs and snails sometimes feed on their foliage, chewing ragged sections out of leaves. Slugs and snails feed on the plant leaves usually at night. To control slugs and snails use diatomaceous earth around your plants. You can also handpick them during the night or use shallow dishes filled with beer as a trap.

Leaves covered by small bumps are caused by scales. These tiny, shelled insects often feed on the undersides of the leaves, causing an unhealthy appearance with yellowish blotches on the upper leaf surfaces. Scrape off minor infestations with your fingernail. Prune out badly infested growth, or use a soft brush and soapy water to gently scrub the scales off the stems. Control scales by spraying insecticidal oil during the growing season.

Most likely cause for these symptoms is a fungal disease - Anthracnose. Keep plants dry when watering to prevent spread. Mow or trim off last year’s leaves in late winter to a height of about 3 inches and remove as much of the debris as possible.

Some Liriope cultivars can be susceptible to root rot caused by Phytophthora, Fusarium oxysporum, or Rhizoctonia solani. As the root systems decay, the plants will discolor from the base upwards. Root rot may occur in sites that have poor drainage or are over-watered. Plants that are showing symptoms should be removed and disposed of immediately before there can be a further spread of the disease.