It all depends on your point of view! All these perennials are hardy and colorful. and some are prolific reseeders. Pictured is Erigeron karvinskianus (Santa Barbara daisy). It will bloom all summer with very little care, but you have to decide if you want it everywhere or if it’s worth it to pull out the little seedlings. The same can be said for Gaura, Geranium incanum and Euphorbia wulfenii.
Another category consists of the plants that spread by rhizomes. A prime example is Oenethera speciosa (Mexican primrose). The delightful single pink flowers abound spring into summer, but with a little water and nourishment, they will overtake their neighbors. And then there’s Origanum “Hopley’s purple”. Like many other ornamental oreganos, it sports lovely mauve-purple flowers in profusion – it just doesn’t know where to stop! Salvia darcyi is spectacular with its bright display of red flowers all summer. Fortunately, the runners that appear are usually welcome, but if not, they are quite easy to remove.
Centranthus, or Jupiter’s beard, is a great perennial, but be prepared for its rather vigorous self-sowing. It is very tolerant of most conditions and needs little water. Flower color ranges from crimson to pink to lilac to white, with a very long bloom period. Gophers do not seem to like it, perhaps because of its…
Hemerocallis (daylily) have arching narrow leaves and lily-like flowers. They are tough plants and reasonably trouble free. A couple of favorites are ‘Stella D’Oro’, a dwarf golden yellow with a longer bloom period than most, and ‘Bitsy’, a repeat bloomer with bright yellow flowers on tall, dark stems about eighteen inches tall. Many flower colors are available including cream, orange,…
Perovskia, or Russian sage, is not a true sage, but it has some similarities. It needs little water, is very tolerant of heat and requires good drainage. Sprays of purple flowers appear in late spring and summer.
The genus Chrysanthemum provides gardeners with some indispensable plants. Shasta daisy (C. maximum) is a wonderful summer blooming perennial that is available in tall or dwarf forms. Flowers can be single, double or somewhat shaggy. C. hosmariense is a great little plant, growing to about eight inches tall and two feet wide. It has finely…
Tulbaghia, or society garlic, is an evergreen perennial with narrow green or green and white variegated leaves. Clusters of small lavender flowers top stems that are one to two feet tall. Provide regular water. Because of the garlicky odor of the leaves, deer tend to leave it alone.
Agapanthus, or lily of the Nile, can be evergreen or deciduous, one foot tall or four feet tall, white or blue flowered. There are several shades of blue, from pale to dark blue-violet. It has green, strap-like leaves with round clusters of flowers rising above the foliage on bare stems. It can take sun to…