<em>Agapanthus</em>: to plant, to grow and to care for

Description and botany

Agapanthus are rhizomatous perennials native to South Africa, also called lily of the Nile, African agapanthus or blue tuberose. Naturally growing on rocky or sandy slopes of the Cape Province, they were discovered in South Africa by a Dutchman in the 17th century. Today, genus Agapanthus includes about ten different species. The genus name Agapanthus comes from the Greek words agapê, meaning ‘love’, and anthos, meaning ‘flower’. Thus, agapanthus poetically means ‘flower of love’. Highly esteemed by Greek philosophers, the term Agapê represented for them the highest form of love, comparable to love of God.

In summer, the flower stems of lily of the Nile rise above the foliage to form at their top a single spherical inflorescence, bluish, violet or white. Each mature plant produces between 20 and 30 flower stems in a season. These stems reach between 30 cm and 1.5 metres in height. Rigid, they resist wind. They end in an umbel measuring between 10 and 20 cm in diameter. This umbel is formed of numerous flowers shaped like a trumpet opening into a star. Each flower consists of six petals fused at the base, which then spread out and separate from one another. They are generally marked with a darker stripe at the centre. Flowers occur in a colour range from blue, azure blue, blue‑grey, blue‑violet, violet and even white.

Foliage consists of strap-shaped green leaves 15 cm to 35 cm long. They form a compact clump 20 to 50 cm in diameter. Leaves are deciduous or evergreen depending on species and varieties. Deciduous species have the advantage of being more cold-resistant than evergreen ones.

Agapanthus flowers are available in many colours: white (Albus), lavender blue (Lavender Haze), sky blue, royal blue (Northern Star), deep blue, bluish‑violet, almost‑black violet (Black Magic).

Agapanthus favour warm, sunny climates but their cold tolerance depends on each variety. Within genus Agapanthus there are less hardy varieties that cannot tolerate temperatures below -5°C. These are generally evergreen. They are mainly suited to coastal or Mediterranean regions where temperatures do not fall below -5°C. Agapanthus have even become emblematic plants of the Breton coast. They require pot cultivation in regions with cold winters.

The other group within genus Agapanthus comprises deciduous varieties that can withstand down to -10°C to -15°C. Hardier, they can be grown almost everywhere in France provided good winter protection. Mountainous regions are still best avoided. This cold tolerance is partly due to new varieties such as Navy Blue, which are popular in cooler regions.

Easy to grow, these blue tuberoses are straightforward to cultivate if site is well chosen. They do not like being moved. They need sun and warmth to flower. Summer watering is essential to encourage flowering, while winter protection is indispensable in cool and cold regions.

Agapanthus are suitable for flower beds as well as borders. They are hugely popular in contemporary gardens, dry gardens and even exotic gardens.

Agapanthus can also be used as cut flowers.

Main species and varieties of Agapanthus

Botanical varieties

Hardiest agapanthus varieties

Our favourite agapanthus species

Agapanthus umbellatus

African agapanthus, Agapanthus africanus, formerly Agapanthus umbellatus, is a reliable choice for gardens. Probably one of the most common in gardens, it produces intensely lavender-blue, luminous flowers borne well above semi-evergreen, strap-like foliage. This very architectural plant is, however, not very hardy (-8°C).

• Flowering time August to October
• Height at maturity 1 m

See the product sheet

Agapanthus Headbourne Blue

Agapanthus Headbourne Blue is widely grown in gardens across France thanks to hardiness down to -15°C. This hybrid is deciduous and bears intensely blue flowers. Reliable choice for gardens.

• Flowering time August, September
• Height at maturity 80 cm

See the product sheet

Agapanthus Navy Blue

Agapanthus Navy Blue is a variety hardy to -15°C. As its name suggests, it produces large umbels of dark-blue flowers, reminiscent of navy blue.

• Flowering time August, September
• Height at maturity 60 cm

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Agapanthus Blue Giant

Hardy to -10°C, Agapanthus Blue Giant is a variety derived from Agapanthus campanulatus. Large, it reaches up to 1.5 m in height and produces dark-blue umbels up to 18 cm in diameter.

• Flowering time August, September
• Height at maturity 1,50 m

See the product sheet

Agapanthus Tinkerbell

Agapanthus variety Tinkerbell is a small agapanthus, 60 cm tall, hardy to -10°C. It has beautifully variegated foliage. Leaves are strap-shaped, green edged with white. Flower umbels are pale blue and measure up to 12 cm in diameter.

• Flowering time August, September
• Height at maturity 60 cm

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Agapanthus Twister

Agapanthus Twister charms with its compact size and especially its bicoloured flowers. Unusual, its small white flowers have a dark-blue base. Hardy to -10°C.

• Flowering time August, September
• Height at maturity 60 cm

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Agapanthus inapertus subsp. pendulus Black Magic

Ideal for creating contrast, Agapanthus Black Magic has one of the darkest flower displays. Its black umbels of buds open into indigo-blue bell-shaped flowers. Simply sublime.

• Flowering time August, September
• Height at maturity 80 cm

See the product sheet

Agapanthus Golden Drop

Agapanthus Golden Drop is popular in small gardens thanks to its compact spread of around 40 cm. Its small flowers are delicate pale blue and its foliage is highly decorative, variegated cream-yellow. This variety is hardy to -10°C.

• Flowering time July to September
• Height at maturity 40 cm

See the product sheet

Discover all our white agapanthus.

Planting Agapanthus

When to plant agapanthus?

To optimise growth and flowering of agapanthus, ideal time to plant is spring. This key period gives plants enough time to root firmly before winter temperatures arrive.

Where to plant agapanthus?

Location is crucial to success when growing agapanthus. These sun-loving plants require warm conditions to thrive. Although some agapanthus varieties can adapt to partial shade, they flower more abundantly in full sun. It is best to avoid planting them under tree canopy, where shade may be too dense for these light-loving plants.

Soil type also plays a determining role for agapanthus. They prefer well-drained, fertile, light soils. Good drainage is essential to help agapanthus withstand cold periods. Sloping sites, embankments or natural rises in ground are ideal, avoiding waterlogging.

Although agapanthus tolerate wind and sea spray, it is sensible to protect them from strong winds that could damage their tall flower stems. Their tolerance of sea spray makes them perfect candidates for coastal gardens.

Agapanthus suit a variety of garden contexts, from dry gardens to Mediterranean, contemporary, exotic schemes, or urban terraces. Their dense foliage and spectacular inflorescences make them ideal for beds, containers or borders. For small spaces or edging, dwarf agapanthus varieties are particularly recommended, combining beauty and adaptability.

Dwarf agapanthus varieties are ideal in pots: Pitchoune Blue, Double Diamond and Golden Drop.

How to plant agapanthus?

Planting agapanthus, known for preferring to remain in place once planted, requires particular attention starting with site selection. Whether planting in ground or in pots, each method has advantages, especially for protecting less hardy varieties from cold.

Steps for planting in ground:

1. Preparing the hole : Dig hole three times wider than size of rootball.
2. Amending soil : Prepare mix composed of one third garden soil, one third compost or potting soil, and one third sand to ensure optimal drainage. For heavy soils, opt for mix of 50% potting soil and 50% sand.
3. Clearing : Remove weeds and stones from hole.
4. Spacing : Place plants about 50 cm apart, which corresponds to 3 to 5 plants per square metre, depending on their size at ripeness.
5. Planting : For plants with bare roots, bury stumps between 5 and 10 cm deep. If plant has rootball, ensure it sits level with soil.
6. Finishing : Refill hole with prepared soil mix, firm well and water generously.

For agapanthus planted in ground, regular monitoring of watering is crucial, particularly during first years and summer periods, to encourage good establishment and abundant flowering after 3 to 4 years.

For growing in pots:

1. Choosing a pot : Select pot slightly larger than rootball or rootstock. Agapanthus prosper when planted fairly compactly.
2. Drainage : Add layer of clay balls at pot base to avoid excess moisture.
3. Planting mix : Use mix of 50% potting soil and 50% sand for filling.
4. Planting : Insert rootball or rootstock into prepared mix.

Growing in pots is particularly suited to compact varieties such as Pitchoune Blue. For more information, see our articles How to grow an agapanthus in a pot?, Best agapanthus to grow in pots, and 5 agapanthus to grow in pots. Note that Agapanthus is among plants that like having roots confined!

In regions prone to frost, it is sensible to plant less hardy agapanthus directly in pots inserted into beds, inspired by French-style gardens. That way, when winter approaches, pots can be easily lifted out of ground and put under cover.

Also find our blog article dedicated to planting agapanthus.

Caring for Agapanthus

Easy to grow, agapanthus require no pruning and are not prone to disease. Their only potential pests are slugs that can eat young leaves in spring on deciduous agapanthus.

Agapanthus prefer fairly rich soils. In open ground, fertilisers are not necessary. In a pot, apply a slow-release fertiliser high in potassium and phosphorus once a year. Supplement with a liquid fertiliser once a month during spring. Applying fertiliser at this time gives your plant a boost at the start of the growing season and promotes summer flowering, which requires energy.

Agapanthus are mainly drought-tolerant in winter. In summer agapanthus require watering 1–2 times per week, ensuring soil is allowed to dry between waterings. This summer watering enables flowering.

During summer, remove faded flowers as they appear by cutting the flower stalk at the base. This prevents the plant from using energy to form seeds and redirects it to producing new flowers. However, if you wish to propagate your agapanthus by sowing, it is necessary to keep faded flowers so they can develop into seeds.

When cold arrives, do not remove leaves from your agapanthus. They will die back naturally in their own time.

In winter, winter protection is essential for your agapanthus. Depending on your climate and varieties planted, follow our advice: “How to protect agapanthus for winter?”

Once your agapanthus plant is established, it is advisable to divide it every 4 to 5 years to restore vigour and encourage abundant flowering.

Propagating Agapanthus

Dividing agapanthes

Best method of propagating agapanthes is division. It is carried out from March ideally outside frost periods. Division at this time allows plant to heal during spring while still dormant and for remainder of season before first winter frosts.

You need a rootstock large enough to divide. To divide, simply:

1. Lift rootstock from soil using a garden fork and spade.
2. Divide rootstock with a knife or spade into 3 or 4 pieces. Each piece must have at least one rootstock, one bud and one leaf if variety is evergreen.
3. And plant your rootstock as described previously in the Planting agapanthes.

For more information on container growing, see our full article on the dividing agapanthes in pots.

Dividing agapanthes multiplies your plants and also restores vigour to older plants.

Sowing agapanthes

Sowing agapanthes is possible but slower and more difficult than division. Expect four years before first flowers from a sowing. Moreover, seeds come from cross-breeding, so colours and shapes of resulting agapanthes cannot be known in advance.

To carry out a sowing of agapanthes, proceed in spring:

1. Use seeds produced during previous year.
2. Sow seeds thinly in a seed tray filled with seed compost.
3. Cover seeds with a little compost.
4. Place tray at around 18°C. Water lightly, continuously.
5. Three weeks later, prick out seedlings into buckets. Watering remains moderate.
6. Six months later, repot your plants into a larger pot.

Combining agapanthus in the garden

Agapanthus pair particularly well with plant and mineral elements. That’s also why landscapers love them. They adapt equally well to a contemporary garden, an exotic garden, a dry garden or a natural garden.

For a contemporary garden, combine agapanthus with stipa, perovskia, miscanthus, ornamental alliums and other bushes pruned into spheres such as crenate holly. Result guaranteed!

For colour, consider creating a palette in shades of blue by pairing them with fescues, nepeta and perovskia. Also match blue of your agapanthus to that of shutters, gate or other garden furniture. Your garden will be all the more enhanced.

Or play with colours complementary to blue‑violet:

• orange: Coppery orange colours of crocosmias, Kniphofias, cannas and daylilies are beautiful with violet‑hued agapanthus such as Royal velvet.
• lime‑green of leaves of alchemilla or agastache Golden Jubilee.
• greys and silvers pair with dark green leaves of agapanthus: artemisias, santolina, lamb’s ear and common sage.

Pair green of agapanthus leaves with grey foliage of artemisia, santolina, or sage (Grower’s Friend). Violet of agapanthus flowers complements orange tones of crocosmias and Kniphofias.

In an exotic setting, pair agapanthus with cannas, gunneras, phormiums or Abyssinian gladioli.

For a more natural style, accompany agapanthus with grasses, apiaceae (formerly called umbellifers) and gaura.