Senecio

( sen - NEE - see - oh )

At-A-Glance Information

This genus of plants is commonly called Ragwort or Groundsel, and includes succulents as well as evergreen and deciduous vines. Species vary widely in exposure and water needs and are native to almost every continent and major climate zone. They can be annual or perennial. Foliage can be green to silver-grey and standard or succulent, and daisy-form flowers are yellow, white, pink, purple, or red-orange depending on the species cultivated. Use these plants in the landscape as groundcovers, vining plants, or standalone specimens. They are ideal for rock and drought-tolerant gardens, pollinator gardens, and container gardens. Take care when planting Senecio in the landscape, as plant parts contain chemicals that are quite toxic to humans and pets if ingested.

Senecio Species and Varietals

Senecio is one of the largest flowering plant genera, containing almost 1,500 species, and is a member of the plant family Asteraceae. The plants in this genus are closely related to those in Curio (String Succulent, Chalksticks), Doronicum (Leopard's Bane), Emilia (Tasselflower), Euryops (African Bush Daisy) and Pericallis (Cineraria). The best growing zones for Senecio vary depending on the species. For more information, see the descriptions below. To find your zone, click here: Zone Map.

Senecio angulatus (Creeping Groundsel, Cape Ivy, Climbing Groundsel, Mile-a-Minute, Scrambling Groundsel)
This species forms a succulent glowering groundcover-shrub that forms a dense, tangled mass of foliage and stems to between 6 and 20 feet tall. Green leaves are satiny, and flowers are yellow with a sweet scent. This species is native to South Africa. It is considered invasive in southern California (United States), the Mediterranean, Australia and New Zealand.

Senecio barbertonicus (Barberton Groundsel, Succulent Bush Senecio, Barberton Senecio, Lemon Bean Bush, Finger-Leaved Senecio, Bush Senecio)
This evergreen succulent shrub is native to South Africa and reaches over 6 feet tall and wide at maturity. Individual plants form fleshy trunks clothed in needle-like green fleshy leaves. Stems point upwards, and are tipped with flower inflorescences in summer. Blossoms are fragrant and yellow. This species can make a good bonsai. The main nursery-sold cultivar of this species is 'Himalaya', which has dense, slender chartreuse leaves and resembles a miniature Pine tree. The species does well in USDA hardiness zones 9-11.

Senecio candicans (Angel Wings, Sea Cabbage, Angel Wings Senecio, Silky Groundsel, Shining-White Ragwort, Alas de ángel)
This species, native to Argentina, forms a clump of broad, serrated ovate leaves that are silver-white in color. Flowers are held in terminal flat clusters and are yellow-orange, blooming in summertime. This species is suited for growing in USDA hardiness zones 8a through 11b. Its primary trade cultivar is 'Angel Wings' (also called 'Senaw', with larger leaves than the straight species).

Senecio cineraria (Jacobea maritima) (Dusty Miller, Silver Ragwort)
This shrubby perennial plant grows best in USDSA hardiness zones 7-10 or Sunset growing zones 4-24, H1 and H2. They are native to the Mediterranean and reach up to 2-3 feet tall and wide with wooly white leaves and yellow flowers. They can get leggy if not sheared from time to time, and need full sun and great drainage for best performance. Cultivar 'Silver Dust' reaches 10 inches tall and has silvery-green leaves.

Senecio confusus (Pseudogynoxys chenopodioides) (Mexican Flame Vine, Orangeglow Vine, Orange Glowvine, Orange-Flowered Groundsel, Llamarada Mexicana, Margarita Mejicana)
This evergreen or deciduous vine is native to Mexico through Hondouras, and grows best in USDA hardiness zones 9-11 or Sunset growing zones 13, 16-24, H1 and H2. Frost will kill this plant to the ground, but it regrows easily. Can reach up to 40 feet tall and wide. Fleshy leaves are light green, and orange-red blooms with golden centers bloom in clusters at branch tips from mid-spring through fall. This vine needs light soil and moderate to regular water and is used on trellises, columns, cascading over walls or embankments or in hanging baskets. Variety 'Sao Paulo' has deeper orange, almost red blooms. This species is considered invasive in Anguilla and Hawaii.

Senecio elegans (Purple Groundsel, Redpurple Ragwort, Wild Cineraria, Purple Ragwort, Strandblommetjie)
Best in USDA zones 8-11, this annual species produces a single upright branching stem topped with inflorescences with flowers in red to purple shades. Individual plants reach up to 8 to 40 inches tall when mature and in bloom. This species is native to South Africa, and is considered invasive in coastal regions of California, Australia, New Zealand, Europe, and the Azores.

Senecio flaccidus (Threadleaf Ragwort, Threadleaf Groundsel, Bush Senecio, Creek Senecio, Douglas' Groundsel, Shrubby Butterweed)
This species is native to central and southwestern North America, where it grows in gravelly, dry soils. It is a fast-growing, short-lived perennial plant that reaches up to 4.5 feet tall. It is woody at the base but herbaceous towards the stem tips. Foliage is green and threadlike and flowers are yellow. Threadleaf Ragwort is suited for USDA hardiness zones 6-10.

Senecio macroglossus (Natal Ivy, Marguerite Ivy, Climbing Senecio, Wax Ivy, Flowering Ivy, Madeliefie-Klimop)
This species is native to southern Africa, and forms a vining plant that can climb vertically or be used along the ground as a groundcover. It has evergreen foliage in its preferred climate zones (USDA hardiness zones 9-11). Leaves are green with light veining, and flowers are butter yellow. Trailing stems can reach up to 10 feet long or more. The main cultivar of this species is 'Variegatus', which produces green leaves with wide cream-white to yellow margins. This species is considered a minor environmental weed in Australia.

Senecio vira-vira (Senecio leucostachys, Senecio cineraria 'Candissimus') (Dusty Miller, Argentine Dusty Miller, Flor de Reina, Vira-Vira, Huira-Huira))
This species is a shrubby perennial that performs best in USDA hardiness zones 8b-11 or Sunset growing zones 4-24 and is native to Argentina. It reaches 4 feet tall and wide, and has whitish leaves cut into pointed segments. Flowers are white but not showy. When grown in full sun, the plant is very leafy and the white is more brilliant in the foliage. In part shade, the plant has a looser form and is more green. Younger plants can be pinched to encourage bushier growth and to keep them more compact. They need little to moderate water.

Caring for Senecio

Take care when planting Senecio in the landscape, as plant parts contain chemicals that are quite toxic to humans and pets if ingested. Plant Senecio in a space in the landscape that receives full sun; ideally they appreciate between 6 and 8 hours of sun each day for the best blooms and overall growth. Ensure that soil is well-draining, rich in nutrients, and has a pH of between 6.0 and 7.5 (slightly acidic to slightly alkaline). These plants naturally grow in rocky, sandy soils, and their soil within the garden should mimic these surroundings. Apply a layer of rock or organic mulch around the planting area to suppress weed growth, maintain consistent soil temperatures, and to increase soil moisture retention. Water new plantings regularly as they establish a strong root system in their new home. At maturity, these plants are very drought tolerant, and are very sensitive to being overwatered. As a general rule of thumb, allow the soil to dry out completely between waterings and make sure that these plants are never sitting in soggy substrate.

Senecio plants grow in naturally lean soils, and do not need to be fertilized. Pruning is simple; remove any damaged, diseased, or dead foliage at any time during the growing season, and remove spent flower spikes to neaten up the appearance of plants and encourage reblooms. If Senecio plants are grown in containers or cramped spaces in the landscape, they will need to be divided from time to time to avoid becoming overcrowded or root-bound. For instructions on how to divide Curio plants, see the Propagation section below. Senecio succulents are considered perennials, and will typically last between 3 and 5 years in the landscape before needing to be replaced. With proper care, these plants can thrive for a decade or more.

Caring for Senecio in Containers
Choose a container that is at least 8 inches tall and deep for most species. Ensure that the container has adequate drainage holes to allow excess water to flow away from the root zone. Fill the container with a well-draining soil mix amended with plenty of sand and perlite. Mulch the top of the substrate with rock or organic mulch after planting. Place the container a spot in the garden that receives full sun; ideally, they should be getting around 6 hours of sun each day for best growth rate and blooms. Water somewhat regularly as the plant gets established in its new home. At maturity, Senecio plants are very drought tolerant and sensitive to overwatering; ensure that the substrate dries out completely between waterings. Senecio plants that have been in containers for a few years may become crowded or root-bound; check for roots attempting to grow through the drainage holes at the bottom of the container. For instructions on how to divide Senecio plants, see the Propagation section below.

Propagation

Senecio are best propagated through cuttings or by dividing existing plants. To propagate your Senecio, follow the instructions below:

Propagating Senecio by Cutting

Gather your materials. You'll need a clean, sanitized, sharp pair of garden shears, rooting hormone, a pencil, and a 3-inch pot filled with well-draining compost or other organic material. A good substrate for propagation of cuttings is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
Between the months of January and March, choose the plant that you'd like to propagate. Ensure that this plant has had a good watering the night before, as this will improve the chances your cutting will take root. Cut one or more 6 inch portion(s) of the end of a branch and strip the leaves off the lower two inches. Make a hole in your planting medium by pushing your pencil into the soil. Dip the end of the stem in rooting hormone, and plant it in your pot. Fill in soil around the cutting to support it, but do not pack it down too much.
Moisten with water, and ensure that the pot has good drainage. Your pot should be kept in warm, sunny conditions indoors (and not in direct sunlight). Water whenever your soil is dry under the top layer. After about four to six weeks have passed, your cutting should be rooted. When you notice new growth, you'll know you have roots.
Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 55 and 70 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring, when you can transplant it to its new home. Ensure that the last frost of the year has occurred before doing this, as it can seriously damage your new plant.

Propagating Senecio by Division
From time to time, Senecio will need to be divided (on average, every three to five years). To propagate via division, you will need a clean shovel, clean pruning saw or hori hori knife (optional), extra pots if you are not going to plant your divisions in the ground, and well-draining soil to fill the pots. To propagate by division, follow the instructions below:

In early springtime, identify the area of plants you're going to divide. Start by loosening the soil around the plant with your shovel, working your way inward to avoid causing damage to the roots. Once you've gotten your plant out of the ground, shake to remove excess dirt. Then, lay it out on its side.
Identify sections of the plant that are healthy and can be divided as well as areas that have died back and can be trimmed off. Divide the plant into sections, each with healthy, sizeable above-ground growth.
Replant divisions in well-draining substrate either in the ground or in containers, and resume regular care.

Problems and Pests

Certain Senecio species are considered invasive in some regions; see the species descriptions above for more information. Check with local authorities before planting. Senecio plants can be susceptible to developing issues with the following pests and diseases: