Euphorbia (eu-four’-bi-ah) plants come from the genus Euphorbiaceae (eu-four-bi-ay’-see-ee) that is made up of a diverse and unusual group of plants.
More than 1600 species of Euphorbia plants (spurge family) are found in almost every region of the world. Not all Euphorbias are succulents.
The name Euphorbia commemorates Euphorbus the Greek physician to Juba, King of Mauritania (part of modern Algeria), who reigned from 25 B.C. to 24 A.D.
Euphorbias have one of the oldest botanical Latin names.
Some are common weeds and others like the Euphorbia marginata (Snow on the Mountain) and the Euphorbia heterophylla (Mexican Fire plant) are annuals.
Others like the Euphorbia pulcherrima the popular Christmas favorite Poinsettia is a perennial bush or tree.
Many succulent Euphorbias resemble cactus and even carry cactus names like:
- Euphorbia mammillaris
- Euphorbia opuntioides
- Euphorbia cereiformis
The Difference Between Succulent Euphorbias And Cactus
Newcomers often wonder what are the difference between cacti and succulent Euphorbias
The Milky Sap
Euphorbias have latex or a milky white sap
In some species, the sap is poisonous, bitter or burning. In others, the white sap makes a low-grade rubber
Cactus rarely have a milky sap except for some Mammillaria species.
The Euphorbia Spines
The spines on Euphorbias come out of the stem
Cacti produce spines from areoles (growth centers) and along the stems
These spines are of three types:
- Woody, sharp, side shoots along the stem
- Small hardened leaf-like appendages forming pairs of spines;
- Woody flower stems which remain on the plant for protection.
The Euphorbia Flowers or Blooms
The inflorescence of Euphorbias is complicated, unlike the showy, simple cactus bloom.
The euphorbia blossom flower cluster is called a cyathium (sy-ath’-ee-um).
Spurge Euphorbia Care
The genus Euphorbia offers a wide variety and complexity of growth forms, euphorbias are amazingly easy to grow.
The euphorbias are not difficult to grow and are low maintenance.
Like most succulents, they must have ample sunshine and air, protection from frost, and careful watering.
Euphorbias Grow In Unique Forms and Sizes
Despite the variety and complexity of forms of growth, growing euphorbias are amazingly easy.
Without special attention, these decorative plants remain attractive for several years.
They may not hold the beauty of flowering plants and their appearance be not as graceful, but their beauty lies in their unique forms and shapes.
Sizes of Euphorbia species range from small 2″ inches high to over 30′ feet tall or more.
Flowering and Fragrance
The blooms are often inconspicuous. The inflorescence of the Crown of Thorns (Euphorbia milii), and the Poinsettia looks like a single flower.
The Euphorbia fruit is three-lobed, with each lobe holding a single seed, bursting when ripe.
Light & Temperature
All varieties need as much bright, direct light as possible. Many grow well in full sun.
Euphorbias do best with day time temperatures of 70° – 80° degrees Fahrenheit and nighttime temperatures of 55° – 65° degrees Fahrenheit.
Watering and Feeding
Water thoroughly and allow to the soil to become dry to the touch before watering again.
Plants do best in low to average humidity.
Feed plants monthly from March to September using a liquid flowering-houseplant food for blooming varieties and on an all-purpose plant food for others.
Soil & Transplanting
When necessary repot to one size larger pot using a cactus and succulent soil mix.
Grooming And Maintenance
Wear gloves and take great care when handling euphorbias as they “bleed” very easily when damaged.
This not only disfigures the plant, but the milky sap is often caustic and poisonous.
It may cause serious injury if it comes in contact with the eyes, the mouth, or an open cut.
In mild climates, many species grow during the winter season.
In colder areas, help keep the plants dormant by keeping plants cool and dry.
Moisture combined with cold can quickly introduce rot.
To stimulate new growth give plants more water as the weather warms up.
Propagating Euphorbia Plants
Propagate plants from seeds or stem cuttings.
Before sticking cuttings into potting soil, allow the succulent stem cuttings to dry and callous for a day or two.
Plants sometimes root slowly.
Some species propagate by offsets; but others, like Euphorbia obesa are propagated from seed since they do not make offsets.
Most euphorbias are quickly and easily raised from seed.
Euphorbia Pest or Disease Problems
Most Euphorbia plants grow with few pest problems.
The most common pests are spider mites, mealybugs and plant scale on some of the leafy varieties.
Overwatering can lead to root rot. Grow plants in well-drained soil and on the dry side.
Popular Euphorbias To Grow
There are so many Euphorbias, to choose from as top-notch houseplants or for use as garden plants.
Below are some of the more popular ones.
- Euphorbia Milii (Crown of Thorns Plant) – blooms all year, formidable spines on long branches
- Euphorbia Trigona (African Milk Tree) – grows into a sizable specimen under house plant conditions.
- Euphorbia tirucalli (Pencil cactus) – small tree or bush, long slender branches
- Euphorbia Obesa (Baseball Euphorbia) – looks like a baseball, with “stitches” along the ribs.
- Euphorbia Caput-Medusae – Wild and exotic-looking, easy to grow, bears small yellow flowers.
- Euphorbia ingens (Candelabra cactus) – impressive succulent species, forms a large tree up to 30′ feet tall, tall stem with numerous spreading branches.
- Euphorbia lactea – excellent plant for a dry, heated apartment, grows well with little care.
- Euphorbia marginata (Snow on the Mountain) – hardy annual, does not transplant well
- Euphorbia myrsinites (Myrtle Spurge) – herbaceous evergreen perennial, aggressive self-seeding tendencies, banned noxious weed in several jurisdictions.
- Euphorbia heterophylla (Mexican Fire plant) – annual, upper leaves blotched with red and white
- Euphorbia polychroma (Cushion Spurge) – yellow-flowering, upright 12″ inches, blooms over a long period in spring and summer.
- Euphorbia rigida (Gopher Spurge) – low-maintenance, drought-resistant bushy evergreen perennial, yellow-green flowers.
- Euphorbia neriifolia (Indian spurge tree) – Oleander-like leaves, spiraling, five angled stems, leathery, glossy leaves.
- Euphorbia cotinifolia – grown for its heart- shaped reddish-purple foliage, likes sun or partial shade, easy to grow.
- Euphorbia Cyparissas (Cypress spurge) – small perennial, yellow bracts used in borders, can become a weed
- Euphorbia Characias (Mediterranean Spurge) – greenish-yellow flowers, attractive to pollinators of all sorts, toxic, invasive.