Rat Infestation Prevention

Algerian Ivy and Star Jasmine, popular ground covers in Southern California, are known to harbor roof rats. For this reason, vector control districts in cooperation with the California Department of Health Services, have developed a list of substitute ground covers not attractive to rats.

Substitute Ground Covers

The list is accompanied by a brief description of each species named. When purchasing these plants, check with your local nursery for more specific information regarding your location.

• Bronze Ajuga (Ajuga reptans atropurpurea): This plant has bronze colored leaves with blue flowers, grows from two to four inches in height, and is considered to be a hardy species. Good in sun or shade; planted 6 to 12 inches apart.
• Giant Ajuga (Ajuga crispa): A large Ajuga plant, this species is very hardy, has metallic colored leaves with blue flowers, and will grow up to nine inches in height. May be planted in sun or shade; space 12 to 18 inches apart.
• Chamomile (Anthemis nobilis): A deep turf is produced by this plant and it can be mowed. Grows to a six inch height if not cut. Good around stepping stones and walkways. Produces a pleasant fragrance when leaves are crushed. Plant in sun, 6 to 12 inches apart.
• Creeping Speedwell (Veronica repens): Dense green leaves with blue spring flowers. This hardy plant grows to a height of six inches. Prefers sun or light shade; plant 12 to 18 inches apart.
• Creeping Thyme (Thymus serphyllum): Small, light green leaves with lavender, white, or pink flowers. Reaches four inches in height, prefers sunny areas and should be planted at 10 inch intervals.
• Dichondra (Dichondra repens): Familiar lawn plant can also be used as ground cover. Grows to three inches in height and withstands moderate traffic.
• Germander (Teucrium chamaedrys): Bright green foliage, resembling mint. Lavender flowers appear in spring. Prefers sun and warm climate. Reaches 10 inches in height, spreads rapidly, and should be planted at 10 to 12 inch intervals.
• Goldmoss Stonecrop (Sedum sp.): This ground cover is a hardy, succulent evergreen which will do well in sun or shade. They will grow to three inches in height and should be planted 6 to 12 inches apart.
• Hahns Ivy (Hedera helix): Good ground cover for erosion control. Grows well in sun or shade to a height of 12 inches. Should be spaced 12 to 18 inches apart.
• Needle Point Ivy (Hedera helix): This subspecies of Hahns Ivy has the same characteristics, except the leaves are pointed. Plant the same as Hahns Ivy.
• Mondo Grass (Ophiopogon japonicum): Evergreen and grass-like, this plant will reach 10 inches in height. Plant’s appearance improves with age, and it is very hardy. Space six to eight inches apart.
• Sand Strawberry (Fragaria chiloensis): Popular ornamental plant in southern California. Very hardy and rapid spreading. Reaches height of eight inches. Plant 12 to 14 inches apart.
• Snow-in-Summer (Cerastium tomentosum): A low spreading perennial with grayish foliage. Does well in hot, dry areas. Grows to six inches in height and should be spaced 18 to 24 inches apart.
• Spring Cinquefoil (Potentilla verna): Has attractive palmate, strawberry-like foliage, dark green in color. Spreads rapidly and produces a bright yellow flower. Grows to six inches in height and should be spaced a foot apart. Very hardy.
• Trailing African Daisy (Osteospermum fruticosus): A good erosion control ground cover. Also called Freeway Daisy, this popular plant blooms through spring and summer. It will reach a height of 18 inches and is very hardy. Plant 12 to 18 inches apart.
• Woolly Yarrow (Achillea tomentosa): Olive-green foliage, spreads rapidly and is good for erosion control. Produces yellow flowers in the spring and is hardy. Grows to nine inches high and should be planted 6 to 12 inches apart.