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

Botany

Tulbaghias comprise 26 species of bulbous or rootstock plants native to South Africa. They grow in meadows and open habitats, sometimes in mountainous regions. They tolerate down to –7 °C, even –10 °C when soil is dry and well drained.

Tulbaghia belongs to family Amaryllidaceae (formerly included in Alliaceae). This family includes Allium (garlic as well as onion, leek, chives, etc.), Agapanthus, Amaryllis, Narcissus, together with snowdrops and Galanthus. Many Amaryllidaceae are therefore cultivated in gardens for ornamental interest, and most of these plants have bulbs or pseudobulbs that allow them to spend unfavourable season underground, in dormancy, to flourish again in spring. As member of same family, it is unsurprising that Tulbaghia resembles a small agapanthus, although flowers are smaller and leaves finer.

Tulbaghia was named in honour of Ryk Tulbagh (1699–1771), Dutch governor of Cape of Good Hope, South Africa. In French, Tulbaghia is sometimes called « Ail d’Afrique du Sud », and in English, ‘Wild Garlic’. species name T. violacea refers to flower colour.

Tulbaghia alliacea: Botanical illustration

Tulbaghias form elegant clumps with linear leaves resembling grass blades. From this foliage emerge erect stems in summer, bearing delicate inflorescences at their tips. Tulbaghia reaches between 40 and 60 cm in height. It spreads slowly thanks to rootstocks, but never becomes invasive.

Tulbaghia offers a long flowering period, generally beginning in July and extending to October, depending on climate. Flowers are carried on long erect stems, rising above foliage. They are grouped in umbels, with up to 20 flowers. Flowering is reminiscent of agapanthus but finer and more delicate.

Flowers are usually pale violet to pink-lilac. There are also white-flowered varieties. Variety ‘Purple Eye’ displays a stronger colour at centre of flower. Species Tulbaghia alliacea is particularly unusual: it bears tubular flowers topped by red–orange crown.

Tulbaghia flowers measure between 0.5 and 2 cm in length and are star-shaped, rather delicate. They consist of six fused tepals, forming a tube at base. Flowers of Tulbaghia simmleri resemble small daffodils.

Flowers are edible and can be used to garnish a salad, for example. Flavour recalls garlic.

Tulbaghia flowers emit a delicate scent (notably in evening). They are melliferous and attract pollinators. Tulbaghia simmleri, sometimes called T. fragrans, has more fragranced flowers than other species.

Tulbaghia in flower! Tulbaghia violacea ‘Variegata’ (photo Wouter Hagens), Tulbaghia simmleri ‘Alba’ (photo Vahe Martirosyan), and Tulbaghia violacea (photo Krzysztof Ziarnek)

Leaves are green, sometimes greyish, long and narrow. They strongly resemble grass leaves. They usually measure between 10 and 30 cm long, sometimes up to 60 cm (as in T. simmleri, for example). Leaves of variety ‘Silver Lace’ are notably streaked with white.

Foliage is semi-evergreen in mild climates, deciduous when grown in cold climates.

When leaves are crushed, they release a garlic scent. Leaves are edible and indeed have garlicky flavour. Chop finely and add to a salad of raw vegetables.

Tulbaghia has fleshy roots and rootstocks by which it spreads. However, it never becomes invasive!

Tulbaghia fruits are triangular capsules, about 1 cm long, which open at maturity to release small black seeds. Tulbaghia can self-seed freely in garden.

Foliage of Tulbaghia violacea ‘Variegata’ and Tulbaghia simmleri, and capsules of Tulbaghia violacea (photos Wouter Hagens / Leonora Enking / El Grafo)

Main varieties of Tulbaghia

Most popular varieties

Tulbaghia violacea Silver Lace - Society Garlic

Tulbaghia ‘Silver Lace’ stands out from other varieties for its foliage marginate with white. It forms a clump with silvery hues, from which delicate violet-coloured umbels emerge in summer. It has received the Award of Garden Merit from the Royal Horticultural Society (RHS).

• Flowering time June to November
• Height at maturity 50 cm

See the product sheet

Tulbaghia fragrans Alba

This variety produces fragrant white flowers. Seen up close, its flowers resemble small daffodils gathered into umbels.

• Flowering time July to October
• Height at maturity 50 cm

See the product sheet

Tulbaghia cominsii Violacea - Society Garlic

This Tulbaghia offers a superb violet–lilac flowering of a very soft shade. In summer and into autumn it bears umbels of flowers made of six fused, very fine petals. Flowers and leaves can be used in cooking as a garlic substitute to flavour salads.

• Flowering time July to November
• Height at maturity 55 cm

See the product sheet

Planting

Where to plant?

Tulbaghia will appreciate being planted in full sun, because good light favours flowering. However, if you live in southern France, you can plant in partial shade, whereas in northern half of country, planting in full sun is preferable.

Tulbaghia prefers well-draining, fairly sandy soils, where moisture does not stagnate, otherwise bulb and roots could rot. If soil is heavy and clayey, better to plant in a pot. It tolerates cold much better when grown in dry, well-draining soil. Tulbaghia also appreciates fertile, humus-bearing soils. It is not very sensitive to soil pH, tolerating both acidic and calcareous soils.

Tulbaghia is ideal in a seaside garden, as it tolerates sea spray and wind very well. It can easily be integrated into a Mediterranean-style garden, alongside oleanders, lavenders and palms. It will fit well in a perennial bed, a border, a rockery or a pot.

When to plant?

We recommend planting Tulbaghia in spring, around May. However, planting in late summer to early autumn is also possible, especially in regions with mild climate.

How to plant?

Planting bulbs in open ground:

As Tulbaghia flowers are quite small and delicate, we recommend planting a large number of bulbs together to obtain a nice mass effect. Tulbaghia has better visual impact when planted in groups rather than individually.

1. Start by working soil to loosen it. You can add well-rotted compost to enrich it, and coarse sand for drainage.
2. Dig planting holes and place bulbs in them. They should be buried under 3 cm of soil and spaced about 20 cm apart.
3. Cover with soil and firm gently.
4. Water generously.

We recommend continuing to water regularly during weeks following planting.

Planting in pots:

1. Choose a pot and place a drainage layer at bottom, for example made of small gravel or clay pebbles.
2. Fill pot with a mix of potting compost, garden soil and coarse sand.
3. Plant tulbaghia bulbs and cover with substrate. They should be placed about 3 cm deep.
4. Firm gently.
5. Water well.

Place pot in a sunny spot, and remember to water regularly.

Tulbaghia violacea (photo Manuel Martín Vicente)

Care

In open ground:

Tulbaghia needs fresh soil in spring; water regularly if it does not rain. Then in summer, when flowering, it becomes much more drought-tolerant. You can therefore reduce watering in summer, autumn and winter.

When you see them, remove withered flowers and damaged leaves. However, it is also worth leaving some spent flowers to allow plant to reseed itself. In autumn, we recommend cutting back clumps to about 4 centimetres above soil. If you live in a cold area, apply a thick layer of mulch (5–6 cm deep) over the stump to insulate it from cold during winter. Tulbaghia will tolerate cold less well if soil tends to retain water.

You can divide tulbaghias every three to four years. This rejuvenates clumps, restores vigour and also encourages flowering.

Tulbaghia is not prone to pests and diseases; on the contrary, its garlicky smell repels aphids! Likewise, the plant appears to secrete fungicidal substances, which help prevent development of fungal diseases. Occasionally, however, snails or slugs may feed on tulbaghia foliage.

In pots:

If you grow tulbaghia in a pot, you will need to water more frequently than in open ground. Potting compost dries out much faster. Be vigilant that tulbaghia does not lack water in spring, and continue to water occasionally during summer. We also recommend adding a little slow-release fertiliser. Similarly, it is preferable to repot every three years.

Tulbaghias grown in pots can be brought in for winter, for example under an unheated, frost-free cold frame. Temperature should not be too high, as the bulb needs a cool environment during winter.

Propagation

Dividing clumps

You can divide Tulbaghia clumps in spring. Wait at least three years before starting to divide them, as these perennials do not like to be disturbed or transplanted. Division nevertheless rejuvenates clumps and gives them more room.

1. Lift a large, well-developed clump at least three years old
2. Separate it into several pieces, making sure each piece retains roots.
3. We recommend cutting foliage back by half.
4. Prepare ground at new location, or prepare a pot with growing medium.
5. Replant, in ground or in pot.
6. Water well.

After dividing, Tulbaghia will take at least two years to flower again.

Sowing

You can sow seeds as soon as they are ripe, then place pots under a cold frame. It is also possible to sow them in spring.

1. Prepare a pot with potting compost mixed with sand.
2. Sow seeds on the surface.
3. Cover with a thin layer of growing medium, then firm gently.
4. Water with a fine spray.
5. Place pot in a bright spot, out of direct sunlight, preferably under a cold frame.

As soon as seedlings are large enough to handle, repot them into individual pots. Wait one year before planting them out in the garden.

Association

Tulbaghia is a small versatile perennial that will fit into a variety of garden styles! As a rule, we recommend planting it in large groups rather than singly to create a massing effect.

You can, for example, incorporate it into a Mediterranean garden. Plant it alongside lavender, rosemary, agaves… Tulbaghias complement agapanthus flowering perfectly, as both have a similar shape (flowering in umbels) and comparable hues. If you want to include trees or bushes, choose, for example, oleanders, palms, fig trees or strawberry trees. Also consider citrus trees. If you live near the sea, this Mediterranean-style planting suits Tulbaghia perfectly. It tolerates sea spray and wind very well!

Tulbaghia can easily be incorporated into a Mediterranean-style garden! Agave mediopicta ‘Lutea’ / Oleander (photo Challiyan) / Tulbaghia, agaves and strelitzia / Fig tree / Agapanthus

Tulbaghia can also be used in a rockery. Create a raised bed in full sun with large stones and a free-draining substrate (add gravel, coarse sand, etc.). Place small houseleeks and sedums between the rocks, and also make use of hardy geraniums, Stachys byzantina and Campanula muralis.

Tulbaghia also works well at the front of borders. You can plant it with perennials that have colourful flower displays. It pairs wonderfully with ornamental grasses: Carex, Stipa, fescue, etc. You can also combine Tulbaghia with agapanthus, or with the mauve-blue flowers of certain Lamiaceae: salvias, nepeta, lavender, Phlomis tuberosa…

Finally, you can also plant it in the vegetable garden. Its garlicky scent helps repel aphids! It appears to have a beneficial effect on carrots and beetroot, while it is better to plant it away from peas and beans. As its flowers, leaves and bulbs are edible, feel free to plant it among other aromatic plants! You can harvest its leaves from time to time, chop them finely and add them to salads to enjoy their garlicky flavour.