VINCA: These beautiful, extremely hardy perennial ground covers which I call creeping myrtle, Elizabeth Riordon called periwinkle, and Rob Call said was vinca are all of the same family. In addressing the differences we learned that creeping myrtle, trailing myrtle, a.k.a. just plain myrtle, are all vincas. This evergreen vinca does best on the North side of the house and is an extraordinarily easy grower. If you desire to control soil erosion in gullies or on hillsides, this would be a good selection.
It does survive in full sun, but prefers a shaded area. It mounds and climbs somewhat like a honeysuckle and with regular watering the leaves appear full and glossy. In the spring, small blue purple flowers give a dainty appearance. Vinca major is a larger version of Vinca minor.
Elizabeth Riordon said a real problem was created when this plant smothered native growth in Ramsey Canyon along the year-round running water course. Most areas of our county are not so fortunate to have this water source, and if care is taken in site selection, this plant can be a definite asset.
Vinca rosea or periwinkle, is the annual version and is available in white, pinks, and rose colors. It is a hardy bloomer and a wonderful bedding plant. These vincas adapt easily when transplanted and are quite popular in our area.
Phyla nodiflora (Lippia repens): Lippia is a low growing perennial used as a substitute for grass. It seems to hug the ground while sending out runners in search of territory to conquer. Its dense green mats can tolerate foot traffic. Lippia is a perfect ground cover for situations where you desire a very low growing perennial. While it spreads readily, it will invade all areas in its path. It choked out native grass which was difficult to mow in our yard, so I encouraged its growth under our old mesquite tree. It transplants easily, grasping new territory with vigor - so use discretion in site selection since once established it will not easily relinquish control. I also transplanted some to cover an ant hill and it seems to be taking hold. Although it does not require mowing, you may want to cut it to rid the plant of the tiny clover-like blossoms which attract bees.