How to Grow Dahlia Tubers in South Africa
Bring colour, shape and armfuls of cut flowers to a sunny summer garden with dahlia tubers. This guide helps you plant, establish and care for the tuber-grown dahlias available from GARDENING.co.za, from the first warm spring days through flowering and winter rest.
Planting time
Plant in spring once frost danger has passed and soil has warmed. In colder interiors, wait for your local frost-free window; in mild areas, still avoid cold, saturated ground.
Position
Choose full sun, fertile soil and dependable drainage. Dahlias dislike shade, waterlogging and a drying root zone.
Planting guide
Set a firm tuber horizontally, eye/crown upward, in a hole about 10–15 cm deep. Space most plants 45–60 cm apart and stake tall types before planting.
Season
Growth and flowering run through the warm season until cold ends the display. Deadhead regularly for more flowers.
Planting dahlia tubers
- Choose a sunny site with loose, compost-enriched, free-draining soil. Improve heavy soil and avoid places where winter or irrigation water stands.
- Check that each tuber is firm, not soft or mouldy, and has a crown/neck with an eye or developing shoot. A detached storage root without a crown and eye cannot make a plant.
- Put a stake or support in place now for taller cultivars so roots are not damaged later. Lay the tuber horizontally with the eye facing up, cover to a total depth of about 10–15 cm, and firm gently.
- If the soil is dry, dampen it lightly at planting. Do not keep an un-sprouted tuber wet: wait for shoots and the first leaves before beginning regular watering.
For containers, select a large, free-draining pot—generally at least 30–45 cm wide and deep—and use a quality potting mix. Compact or border forms are usually the easiest choices for containers; match support to the plant as it grows.
Growing and flowering care
Once growing strongly, water deeply at the root zone whenever the upper soil begins to dry, then let excess water drain away. Mulch around, not against, stems to steady moisture and suppress weeds. In hot, dry interiors, check soil often; in humid coastal gardens, give plants generous space and keep foliage dry where practical to improve airflow.
Feed modestly after establishment with a balanced or flowering fertiliser according to its label; avoid pushing soft leafy growth with excess nitrogen. Tie stems as they lengthen. Pinching the main shoot above several pairs of leaves can make vigorous plants bushier; leave naturally compact plants unpinched if you prefer their simple form.
Remove faded blooms back to a leaf joint. Cut flowers in the cool of the day and place stems in water promptly. Watch young shoots for slugs and snails, and inspect for aphids, mites and powdery mildew. Remove badly diseased material; do not compost plants showing virus-like mottling, distortion or severe stunting.
South African timing and winter care
Frost-prone interior
Plant only after local frost risk has passed and soil has warmed. Lift and store tubers before freezing soil can damage them.
Winter-rainfall areas
Use raised or exceptionally well-drained beds. A wet winter can rot dormant tubers, so lifting and protected storage is the safer choice where drainage is doubtful.
Humid coast and KZN Midlands
Give plants sun, spacing and airflow. Water the soil rather than the blooms, and remove spent flowers and diseased leaves promptly.
Hot, dry or subtropical interior
Mulch and water deeply to keep roots evenly moist in heat. Provide support early and protect plants from damaging wind.
Lifting, dividing and storing tubers
After cold has ended growth, or before a damaging frost in cold districts, cut stems back and lift carefully well outside the crown. Brush off loose soil and dry only healthy, undamaged clumps before storage. Keep labels with each clump.
Store in a dark, cool, frost-free place in open-topped boxes or crates with a dry-to-slightly-moist insulating medium such as vermiculite, coir, paper or dry potting medium. The aim is balance: no condensation or sealed, wet storage that promotes rot, and no prolonged desiccation that shrivels tubers. Check periodically, remove rotten material and adjust the medium only if tubers are drying severely. Divide in spring when eyes are easier to identify; every division needs a viable eye attached to crown tissue.
Troubleshooting
No shoots
Cold, wet soil can delay growth or rot a tuber. Check drainage and wait for warm conditions; only plant firm tubers with a crown and eye.
Weak or falling stems
Stake early, space adequately and avoid excessive nitrogen. Tall or large-flowered plants need more substantial support.
Few flowers
Increase sun, deadhead, keep roots evenly moist and avoid crowding. Excess leafy growth can indicate too much nitrogen.
Rot in ground or storage
Improve drainage, stop overwatering dormant tubers, dry lifted clumps properly and discard soft or mouldy tissue promptly.
Pet safety: Dahlia species are toxic to dogs, cats and horses. Keep tubers and cut plants away from pets and seek veterinary advice promptly if ingestion is suspected.
Choose your dahlia tuber
Pick a favourite flower form or colour, then use the matching product link below. Each product returns here to the same planting and care method.
Dahlia Semi-Cactus - Bora Bora - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Border - Autumn Fairy - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Border - Park Princess - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Border - Graz - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Border - Bluesette - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Border - Carola - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - Anja G.J. - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - Mev. Cl. Andries - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - Einzi - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - Ma Jolie - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - Belmonte - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - Preference - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - Good Earth - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - Anderson - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - Alfred Grille - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - Colour Spectacle - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - Cheerio - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - Snow Country - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - Edna Comstock - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - House of Orange - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - Eclat - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - Nepos - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - Rosella - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - Edinburgh - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Dinner Plate - White Perfection - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Dinner Plate - Kelvin's Floodlight - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Dinner Plate - Red - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Dinner Plate - Lavender Perfection - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Dinner Plate - Otto's Thrill - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Terrace - Samba - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Terrace - Tango - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Terrace - Foxtrot - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Terrace - Rumba - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Terrace - Rock 'n Roll - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Terrace - Salsa - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Pompon - Serenity- 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Pompon - Amusing - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Pompon - Bell Boy - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Pompon - Lolly Pop - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Top Mix - White - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Top Mix - Yellow - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Top Mix - Orange - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Top Mix - Red - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Top Mix - Rose - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Pompon - Deepest Yellow - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - Yellow - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - Orange - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - Red - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - Pink - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - White - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Cactus - Orange - 2 bulbs
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Natal - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Vancouver - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Wittem - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Checkers - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - Rip City - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.
Dahlia Decorative - Santa Claus - 1 bulb
Plant this dahlia tuber using the guide above, then give it room, sun and support appropriate to its eventual growth. Keep its label with the plant so its flowering form stays identifiable at lifting time.