Creeping Jenny, also known as moneywort or lysimachia, is a low growing ground cover that expands swiftly and can be an effective shade-loving plant. If you plan to grow Creeping Jenny, check with your county extension service first, as it is considered an invasive plant in some parts of the US. There may be prohibitions against growing it in your state. The plants grow about 2 inches tall and will spread as much as it can.
The leaves of the plant look like small round coins and because of this, in England the plant was called "Twopence." In America, it came to be known as moneywort. The name "Creeping Jenny" is believed to be a corruption of "creeping chinny" because the herb was once used to treat "chinny" or whooping cough.
Creeping Jenny is a perennial, hardy in USDA zones 3 through 8. It does well in sun or shade, and, under optimal conditions, will quickly overtake your garden. It is, however, easy to control if you stay on top of it. Creeping Jenny has small round leaves and bright yellow or white flowers in late spring or early summer. Some people may be allergic to the pollen. It is grown primarily for its foliage; which is evergreen in most locales, unless it gets too much wintertime sun.
Other than light and moisture, creeping Jenny has few requirements. It will grow well in most soils. Left on its own, it will start to take over the garden. For this reason, it should be cut back to ground level in the fall. Another option is to just mow it a couple times during the summer. To propagate new plants, divide old plants in the spring in cold climates or in the summer where it is warmer.
Start Creeping Jenny in seed flat outdoors in the fall. Sow seeds on the surface and put flats in a shady area. Sink the flats into the ground to keep them warm, and cover with a sheet of glass. The seedlings will germinate in one to three months. Once the seedlings begin to trail, they are ready to be transplanted into the garden. Choose a sunny or partially shaded spot for the new seedling. Space the seedlings about 12 inches apart in moist soil. Water regularly as Creeping Jenny's likes moisture.
If you over water or fertilize a Creeping Jenny, it will reward you with rapid and extravagant growth. To help contain it, don't fertilize and restrain yourself on the watering. Growing it in rich soil will also promote rapid growth while poorer soil will slow it down. This is one of those plant-it-and-forget-it plants, but don't forget it entirely unless you want your flowerbeds and yard to disappear under its trailing growth.