If you are looking for an all-around excellent plant for a mostly sunny garden, you might want to investigate euphorbias. They are among the precious few plants that are rarely sampled by deer, gophers and rabbits. And few insects attack them. Their milky sap can be irritating, or in extreme cases, even toxic, but most gardeners just wear gloves when handling the plants and seem to have no problem. There are even claims from some gardeners that a garden rich in euphorbias will have few resident gophers; I can't vouch for that but do know that mine have never been eaten by any of the hungry mammals that can wreak such havoc among other plants.
Among their many virtues, euphorbias are extremely drought tolerant, mixing very well with succulents and plants native to the Mediterranean regions of the world. Sizes range from soil-hugging ground covers and strange tiny species that resemble cacti, to large woody plants reaching 30 feet. Some have beautifully colored foliage. Flowers are produced in large clusters; bright chartreuse bracts form a cup around the tiny true flowers in a contrasting color, usually red, pink, gold, maroon or sometimes rich brown, adding up to a bright and unusual show. Stems on some are red E. 'Red Martin' and a few, such as E. 'Tasmanian Tiger', even have strongly variegated foliage. In spring, I saw various euphorbs widely used on a tour of East Bay gardens, and they were knockouts among other drought-tolerant plants.
Euphorbia is a very large genus, numbering about 2,000 species. They can be annuals, biennials, perennials and evergreen or deciduous shrubs and trees. Most are quite cold tolerant, but some are tender. We all know E. pulcherrima, the poinsettia, which is borderline hardy here in our mildest areas; some gardeners in protected sites can successfully grow these plants outside, eventually having them become large shrubs.
If you look closely at what we call the flower on a poinsettia, you will notice that the bright red parts are modified leaves [bracts] and the true flower is the small yellow structure in the center of the red bracts.
Many other euphorbias also have colorful bracts that give the effect of flowers. On most, flower and bract clusters last for a very long time. Some begin blooming in early spring and are still going strong in autumn, adding bright and reliable color in the garden. They can also be excellent cut flowers. Before using them in arrangements, dip stems in boiling water or pass the end over a flame for a few seconds so the sap won't bleed.
Euphorbias can produce abundant seed, formed in a dry capsule that releases explosively, shooting seed several feet away. Some gardeners find that they have many seedling plants showing up some distance from the parent plant, but the seedlings are easily pulled and rarely become pesky. The plants like well-drained soil, require little or no water once established, and depending on the species, will be happy in sun or bright shade.
Look now for E. dulcis 'Chameleon,' a cold-hardy perennial, forming a mound to 2 feet high and wide. New growth is burgundy, changing to dark green with maturity. The showy flower clusters are greenish yellow with a purple overlay. Colder fall temps induce the leaves and bracts to turn rich purple. They are drought tolerant, for sun. E. 'Dean's Hybrid' has brilliant acid yellow bracts that bloom from early spring through summer and then rebloom in fall. A 2-by-2-foot mound with tidy narrow foliage, they are cold hardy in all local areas. And E. myrsinites, with steely blue gray leaves, has an interesting form and bright yellow bracts in early spring. Cut old stems out as they fade, for a tidy plant, and to encourage strong new growth.
-Sharon Hull
