With regards to variety and fragrance, the South African bulb richness is unmatched in world ornamental horticulture, especially our spring-flowering species from the Western Cape. Today, they are cultivated and refined worldwide and new species are discovered and named every year. These are especially the Iris family (Iridaceae), chincherinchee and the 'viooltjie' family (Hyacinthaceae). These include plants such as the kalkoentjie or little turkey (Gladiolus), 'kelkiewyn' (Geissorhiza), froetang (Romulea), Watsonia, Cape Cowslip (Lachenalia), Freesia and Babiana.
The most important component to achieving success with your plants at home or garden is regular attention and love.
What do bulbs need to thrive?
To better understand the breeding requirements of our spring-flowering bulbs, we need to look at how they survive in the veld. Our local fynbos and other Cape flora are in harmony with the environment.
The various plant groups have several adaptations to survive.
- The annuals escape the summers by growing their life cycle within the favourable cooler and wetter months, flowering and producing seeds. The seed, therefore, survives the dry summer.
- Succulents on the other hand store their water in their leaves or stems.
- Bulbs use a unique method. They kick off their beautiful clothes in the hot arid summers and disappear into an underground existence, only to stick their heads out again in autumn. During this time they store as much food and water as possible for the winter and invest in their fleshy parts for the upcoming season.
Even if there is little rains during the winters, the little moisture can be used more effectively because the days are shorter, the sun is not as hot and the soil does not dry out as quickly.
Bulbs also need solar energy for growth, many of them have large leaves relative to their bulbs and are also usually carried close to the ground where they use some of the solar-heated soil to get growth energy.
Underground bulbs also have problems, such as soil fungi, insects and moles but for this they are also adapted. Some bulbs, especially the shallow growing bulbs are poisonous, making them inedible. The more nutritious and edible the deeper and harder to reach the bulb.
Some bulbs produce many small bulbs in case the mother plant is eaten up so that one of her children will survive. Others will even regenerate from bulbous scales. Some also occur between rocks in crevices where it is almost impossible for the moles to reach. Some bulbs sit on top of the ground with only their roots and the basal portion underground.
The underground parts of bulbs also vary a lot. The true bulbs (e.g. violets) have densely enclosing fleshy bulb scales, while others have tubers and fleshy rhizomes. Watsonia bulbs have underground corms. The latter is just a tuber with a sieve-like dress around it. The tubers of most bulbs are underground but occasionally, as in the case of the pregnant onion (Ornithogalum longibracteatum), they can be above ground.
How to grow bulbs in your garden
Winter-growing bulbous plants are adapted to cope with little. Most growth requirements require a sunny environment, adequate air movement, well-draining soil and a summer rest period when the bulbs do not need moisture. The natural habitat of our attractive winter-rainfall bulb species is fynbos (strandveld) and Succulent Karoo. In nature (habitat), bulbs grow mostly in sandy poor soil in a sunny environment and are important factors to consider in their successful cultivation. The soil should therefore be very sandy and well-drained and in a sunny corner.
Bulbs also thrive in rock gardens and containers. As for the container, bulbs can be planted in almost any kind of soil but must have the necessary drainage. Place crushed potsherds, coarse gravel or pebbles as a bottom layer. A layer of compost can now be placed on top of the gravel and the rest of the container can be filled with sand to about a centimetre from the edge of the container.
The bulb planting depth depends largely on the bulb size and as a rule is planted as deep as about three times their height. Once the bulbs have finished flowering and the leaves wither in early summer, the container can be stored in a dry cool place for next autumn. The bulbs can also be taken out and stored in a paper bag in a cool place for the duration of the summer. It is always advisable to soak the bulbs in a fungicide before planting them.
Beautiful indigenous bulbs for your garden
There are so many types that actually make it difficult to choose.
Tjienkerientjee | Ornithogalum spp.
Easy growers with true bulbs and nearly 60 species in the RSA are widespread, most with white flowers. Ornithogalum thyrsoides are grown the widest and up to 50 cm tall and with white flowers. Ornithogalum maculatum grows about 8-30 cm high with orange-coloured flowers. Ornithogalum dubium with yellow to orange flowers from 10 cm to 30 cm tall. Plant about 4-6 cm deep and about 8-12 cm apart.
Pipes, red pipe, wash pipe | Watsonia spp.
One of our most beautiful indigenous sphere groups with almost 50 species that are widespread in the south-western, southern and eastern parts of South Africa. Recommended species include Watsonia coccinea, W. laccata, W. spectabilis and W. humilus. The red pipe is a small species from 15 cm to 25 cm high with colours ranging from red, purple to pink. Watsonias' rooted tubers can be planted about 4-6 cm deep and 10 cm apart.
Harlequin Flower | Sparaxis
Real jewels among our bulbous plants. It is only a small group with only six known species. Striking are their multi-coloured flowers. These are smallish bulbs that have been cross-bred in Europe for some time (Sparaxis grandiflora, S. elegans and S. tricolor) and are bred and are freely available in the trade. Feel free to buy them now for a nice spring show. Plant them about 5 -7 cm deep and apart. The Cape buttercup (Sparaxis elegans) with attractive salmon-pink to white flowers and the three-colour velvet (S. tricolorum) are recommended (3-coloured with orange, yellow and black).
'Bobbejaantjie' | Babiana
Their scientific name is derived from their popular name 'bobbejaantjie'. A large group of about 60 South African species. There are attractive varieties and cultivars available. The most beautiful cultivars were cross-bred from theBabiana stricta hybrids. Plant about 4-6 cm deep and 4 to 6 cm apart. Keep well watered every two weeks. Their smoky tubers can be stored in early summer after the flowers and leaves have withered. Babiana rubrocyanea is one of our most beautiful species of moody bright blue flower petals with red on the inside. Grows to about 15-20 cm high. Babiana pygmaeae has large cream-coloured flowers. Their seeds should be sown in the fall. Babiana angustifolia has violet to blue flowers with dark black-purple to dark red spots.
Freesia | Freesia
Freesias are known for their delicious floral fragrance but unfortunately, their fragrance can largely go to waste with crossbreeding. Freesias bloom in late winter and early spring. They are arranged around 40 cm high, with trumpet flowers arranged like a comb (and projected upwards). Plant them about 4-6 cm deep and about 5-7 cm apart. Around eleven species occur in the Western Cape. The white comb (Freesia alba), rose freesia (F. andersoniae) with rosy pink fragrance flowers. The feather (F. refracta) with attractive cream-yellow flowers.
African corn lilies | Ixia
A striking Cape group with almost 45 species. They also have tufted tubers, and long-legged bulbous plants up to 70 cm tall. Plant their tubers about 4-7 cm deep and about 4 cm apart. They are striking in groups. The star anemone (Ixia maculata) grows up to 60 cm tall with yellow to orange flowers. The green colossus (Ixia viridflora) with the strangest pale green flowers and inflorescences up to 1 meter high.
Cape cowslip | Lachenalia
Some of our most beautiful and sung by Leipoldt, a large group of more than a hundred types of measuring stables from the Western and Northern Cape winter rainfall regions. They are true bulbous plants with small bulbs and stems 8-25 cm high. Their attractive tubular flowers are sometimes aloe-like and striking. Plant shallow (1 cm deep), about 2-5 cm apart. Our Lachenalia species are also a genuine South African group that is bred today. Every year new species are still named which again shows how unknown our flora is.
What makes Lachenalia such excellent plants is that they grow easily and do well in containers on a porch or window sills. They are especially useful for people in apartments with limited space. They require a well-drained sandy soil consisting of one part sand and one part compost. They should be kept completely dry in the summer. Violets can be easily propagated from seed or division or leaf cuttings and are not ashamed to flower. They also cross easily and new cultivars can be easily developed. However, they require a sunny environment.
Species recommended include stone colossus (Lachenalia aloides) and its varieties (orange, yellow), sand colossus L. rubida (red), red clove (L. bulbifera) (red), blue-violet (L. orchioides) (cream to blue ), white-violet (L. orthopetala), purple-violet (L. splendida) and the green-violet (L. viridiflora). For more information, please consult the violin specialist Graham Duncan's book "The Lachnalia Handbook" (1988).
Arum lily | Zantedeschia aethiopicum
The white arum cup is one of our most beautiful and easy-growing growers. It is also not selective of the soil where it grows and can even grow in shallow water. A fast grower and striking with large conspicuous flowers on stems up to 70 cm in height and borne in early spring.