Useful Ground Cover Plants – The best ground cover plants are evergreen. St. John’s wort (Hypericum) can be grown in a shady part of the garden where its bright yellow flowers will grow out of the darkness. Rose of Sharon (Hypericum calycinum) flowers from early summer to early fall. It makes a good specimen plant in non-shady places, too, but if planted in a border it can be invasive.
The periwinkles (Vinca) are excellent at covering the ground but can be invasive too, so plant them in woodland where they will have to struggle a little. Vinca minor grows to only just off the ground. It normally has pale lilac flowers but white and dusky red forms are attractive and slightly less invasive.
V. major will reach 30 cm (12 in) and climb into nearby shrubs. It can be difficult to control when grown among other plants.
Ivy (Hedera) does well in shade. Irish ivy (Hedera helix ‘Hibernica’) has large green leaves and will grow in dense shade. It is a good maintenance-free plant grown in a north-facing, little-used part of the garden.
Dead nettles (Lamium) make excellent ground cover plants under trees. Lamium galeobdelon ‘Silver Carpet’ has yellow flowers and evergreen leaves heavily spotted with silver. It is invasive but not difficult to pull up where it has outgrown its space.
When planting under trees it is vital to prepare the soil well and to remove all weeds such as couch grass, nettles, and ground elder, otherwise their roots will entwine with your plant roots to disastrous effect.
In a sunny, well-drained spot, the rock rose ‘Helianthemum nummularium’ grows vigorously and makes excellent colorful ground cover. There are many named varieties in pretty shades of red, yellow and white. They should be cut back severely with shears when the flowers are over in summer or they will become leggy and lose value as ground cover. Do not prune in spring or you will remove the flower buds for the year.