The Lachenalia Homepage
contents:
Introduction
History
Description
Distribution
Conservation
Propagation
Breeding
Applications
Pests & disease
Species
Introduction
The cape region of South Africa is among the most botanically diverse areas in the world, and the flora is not only diverse but unique. Many species and even genera grow nowhere in the world but this small region. Bulbs are especially prevalent in the flora, and the historical Dutch prescence in South Africa explains why the Dutch dominate the world's bulb trade. There are many species that haven't been in the trade much, but which has significant horticultural merit. Many species of Lachenalia fit this bill.
Lachenalia (Hyacinthaceae) is among the well-represented liliaceous genera endemic to southern Africa. The genus has a long history in South African and European horticulture, and efforts continue today to develop its commercial potential as a sought-after ornamental plant. Despite taxonomic uncertainties, numerous hybrids have been produced for the international ornamental plant industry.
History
Bulb enthusiasts have prized Lachenalia for centuries. When they were first discovered in 1652, by explorers for the VOC (the Dutch East India Company) entering the interior of South Africa. During their journey they collected a wide variety of bulb plants which were taken back to Europe. These plants were extremely valuable and were coveted by wealthy European collectors. By 1784, the passage of time had seen a large collection of Lachenalias come into being in the gardens of Schönbrunn Palace in Vienna, Austria where they were originally categorized as Hyachinthus, but re-categorized in 1784 as Lachenalia, named after Swiss botanist Werner de la Chenal.
The plants drew the attention of Baron Nicholas Joseph Jacquin who decided to study them. He named the plants "Lachenalia" after Werner de Lachenal a famous professor from Basel, Switzerland. These plants have been known as Lachenalia aloides ever since. They were instantly popular. The East India Company began distributing lachenalia bulbs to flower lovers world-wide as early as the mid-1600s. T
Descriptions date back to the earliest plant-collecting exploits of the Dutch East India Company, circa 1650. Initially called Hyacinthus (and by other epithets, too, since these were the days before Linnaeus' binomial nomenclature system created a uniform standard for botanical names), the bulbs were classified as a unique genus in 1784 when they were named after Swiss botanist Werner de la Chenal (hence Lachenalia).
The genus Lachenalia is endemic to southern Africa, and is the largest genus in the family Hyacinthaceae, containing ±110 species that occur in Namibia, the Free State and the Northern, Western and Eastern Cape provinces, but with the vast majority occurring in the winter-rainfall regions of the Cape. The genus is named after Werner de Lachenal, 1739-1800, professor of botany at Basel, Switzerland. The species is named after Mr. J.W. Mathews, the first Curator of Kirstenbosch Botanical Garden, who discovered this species in 1923. There are no common names recorded for Lachenalia mathewsii, but lachenalias in general are referred to as lachenalia, or viooltjie, a name derived from the squeaky note, suggestive of a small violin (viooltjie in Afrikaans) that is produced by rubbing two flower stalks together and not from any real or imagined resemblance to violets (also viooltjie in Afrikaans). The name would generally be prefixed by a qualifying description e.g. in this case it could be called geelviooltjie (yellow viooltjie). In Europe and America lachenalias are often commonly called Cape cowslips, but this name is a bit misleading, as they don't really bear any resemblance to the wild British cowslips (Primula species).
Desription
Lachenaleas are of the hyacinth family. This ones blossom consists of numerous tiny bell-shaped purple flowers on a stock, forming a pyramid-shaped bloom that becomes more rounded & elongated as it ages. Also as it ages, the yellow-tipped purple stamins become longer & showier poking out of the tiny bells. This rather extravagant & sweet-smelling late winter or spring.
Most lachenalias produce just one pair of leaves, though there are exceptions to this rule under cultivated conditions. Leaf form in the majority of species is wide and fleshy, but again there are exceptions. The leaves of L. contaminata, for instance, are thin and grass-like. Some species bear leaves with handsome dark spotting, while others display leaves that are notched with distinctive pustules (blister-like bumps).L. aloides is easily recognized by its lanceolate or lorate, usually heavily marked leaves, and its inflorescence of pendulous, cylindrical flowers in which the inner perianth segments protrude conspicuously.
Lachenalia mathewsii is an attractive, deciduous, winter-growing bulb, standing 10-20 cm tall. It produces two distinctive, narrowly lance-shaped, tapering leaves. The leaves are unmarked, fresh green in colour and covered with a greyish bloom. The inflorescence is a raceme of bright yellow flowers, each flower bell-shaped and held more or less perpendicular to the main stem, with conspicuous green spot-markings near the tip of each tepal. The flowers have a mild spicy scent and are pollinated by honey bees. The fruit is a capsule containing small, hard, shiny black seeds.
Lachenalia blooms are usually found on single spikes or as racemes on top of a thick and, usually, mottled stem. These flowers can be found in three basic shapes: tubular, bell-shaped or urn-shaped. They don’t tend to be scented but a few species do have a delightful, powdery sweet fragrance.
Most of the species of lachenalias have only one pair of leaves but there are some exceptions. Most of the leaves in the various species are wide and fleshy with a few exceptions like the Lachenalia contaminate where the leaves are thin like grass. Some varieties have leaves with dark spotting and there are some with leaves that have distinctive pustules or blister like bumps.
The most commonly cultivated species of the Lachenalia is the Lachenalia aloides. This species is easily acquired from specialist shops as it is the most popular member of the genus. It is the most colourful variety and the leaves are also colourful. The leaves have purple tiger stripes and the tubular flowers are bright yellow accented with red and green. They are seen in winter and early spring where they tend to hang down from a ten inch, richly variegated, stalk.
Another Lachenalia strain, Lachenalia viridiflora, blooms around thanksgiving. These flowers have a unique colour that is neither turquoise nor green. This plant as not as flashy as Lachenalia aloides but is more popular among garden enthusiasts. Other varieties of Lachenalia include the Lachenalia mutabilis and Lachenalia framesii. These strains produce tiny flowers that are delicately coloured. They look more like miniature orchids than a typical Lachenalia. The inner petals of the Lachenalia mutabilis are chartreuse with outer petals of maroon and purple. The Lachenalia framesii have inner petals of magenta with outer petals of green.
Distribution
Some species of Lachenalia are abundant throughout the Cape. Others have a narrow range of distribution—an entire community might exist on a single isolated rock outcropping. This sparseness of dispersal is the reason why new species continue to be discovered. But it's also the reason why so many are at risk. Their habitats are under constant threat from environmental flux (drought and fire), from human agriculture and development, and from invasive plants imported to South Africa from similar climatic regions, such as Western Australia.This is a widely distributed, complex species consisting of many different forms. It is almost always associated with rocky habitat and occurs in coastal areas from Lamberts Bay to the Cape Peninsula, east to Bredasdorp, and as far inland as the Worcester district.
Conservation
One of the most pressing reasons to cultivate these bulbs, besides their charm, is for conservation purposes. Even if a species is "lost" in the wild, it is not lost to science, and the genetic material held in cultivated collections can be tapped for potential reintroduction into the wild. Adopt a Lachenalia—you'll not only be bringing a beautiful plant into your home, you'll be helping to protect the biodiversity of the planet.
Lachenalia mathewsii is an endangered plant that was for a time considered to be extinct in nature, as it had not been collected from 1943 until Queenie Paine and Hertha Bokelmann found it again in 1983. It is now known from only one locality on the west coast of the Western Cape, the rest of its habitat having been ploughed up for agriculture. Nevertheless, since its rediscovery, Graham Duncan, the curator of the bulb collection at Kirstenbosch, has increased the number of plants in the nursery, and seed and plants have been made widely available, so that it is now grown in bulb collections all over the world. Seed is available from the Seed Room at Kirstenbosch.
Cultivation
These South African bulbs are found in rocky soils that are nutrient poor so it is better to simulate this soil for cultivation. Use a well drained mix with minimal to no humus in it. It is best to grow these bulbs in a mixture of three parts bark, one part grit and one part sand. Some people also suggest using coarse sand mixed with some compost. There is no need to fertilize the soil. You can use low nitrogen fertilizer but it is best if you don’t.
Once the bulbs have been potted, you have to water them but there is no need to water again until the leaves appear above the surface of the soil. Never let the soil dry out completely as this can trigger dormancy and stress the bulbs. A sign of a problem brewing in the bulbs is the leaf tip turning brown. Don’t water Lachenalia bulbs too often because too much water in a poorly drained soil will rot the bulb.
As the weather turns warmer you will find the leaves of the Lachenalia will start to turn yellow and wilt. These bulbs are cool weather growers so reduce the water supply for them until the leaves are all yellow. At this point you have to stop watering. Don’t induce dormancy in the bulb till the bulb reaches this point. If the bulb has green leaves – water it. During the summer dormancy period move the containers of bulbs to a dry place.
The best time to repot Lachenalias is around August and September. This is because the cool evening temperatures and warm days tend to stimulate good growth of the roots in the fall. The ideal temperature is between 10°C to 21°C (50°F to 70°F). Lachenalias can tolerate more shade than other South African plants but they still need as much sunlight as you can provide. They tend to lose their mottled leaf look and become lank when they don’t get enough sunlight.
Bulbs begin to become active as soon as temperatures begin to fall after the summer. Once temperatures drop, pots should be watered thoroughly once and then wait until new growth appears. Infrequent heavy irrigation is preferable to frequent, light watering which can lead to rotting of the bulb. It is always preferable for the media to be slightly dry rather than too wet.
Foliage will begin to yellow as temperatures rise in summer and water should be completely withheld and containers moved to a cool, dry location once the foliage has withered. Lachenalias are an adaptable lot and relatively easy to cultivate. No pretreatment, such as a cold period, is required. In early autumn, place six to 12 bulbs in a 6-inch pot, depending on the size of the bulbs and their leaves. Plant the bulbs 2 to 3 inches deep. Lachenalias don't mind being crowded—in fact, they give a better display when planted this way. They are shamelessly promiscuous, producing numerous bulblets and offsets that can be separated and repotted.
South African bulbs are found in nutrient-poor, rocky soils. To simulate this in cultivation, always use a well-drained mix, with little or no humus. I grow bulbs in a mix of 3 parts bark, 1 part sand, and 1 part grit. In his Lachenalia Handbook, Graham Duncan recommends coarse sand mixed with a little fine compost.
Because lachenalias naturally grow in poor soils, there is no need to fertilize. In my experience, the plants do respond very well to low-nitrogen amendments. But err on the side of less fertilizer!
Water your bulbs once they have been repotted and not again until leaves appear above the soil surface. Then, as the pots dry out, give them a good soaking. Never allow the bulbs to dry out completely, as this could trigger dormancy or create unnecessary stress (you'll know there's a problem if the leaf tips start going brown). Too much water in a poorly drained soil, of course, spells one thing: R-O-T. "Love is not water" is a mantra for bulb growers.
Leaves will begin to yellow and wilt as the season progresses and temperatures rise (which is why these bulbs are cool-weather growers!). Reduce the amount of water you supply your bulbs until the plants are at this yellow stage, at which point, stop all watering. Never induce dormancy by withholding water before the plant is at this stage. If the bulb still has green leaves—water it! During summer dormancy, simply move your containers to a dry place.
Re-potting can begin in August or September. Cool evening temperatures and warmer days will stimulate root growth in the fall. Daily temperatures should range between 50 and 70 degrees Fahrenheit. Lachenalia species can tolerate a little more shade than their other South African peers, but require as much sun as you can provide. If the bulbs are placed in a situation that is less than bright, they will lose their mottled leaf appearance and become lank.
Lachenalia can be described as gregarious plants liking to be in groups and certainly the display one achieves is enhanced by semi mass planting. In the Australian climate I find that the amount of soil in a small (4" pot) pot is insufficient to maintain moderate temperatures and moisture levels. If the pots were plunged in some medium such as gravel or course sand etc. the effect of small pot size might be minimized. I usually aim to have enough bulbs to comfortably fill a 6" pot but where numbers are low I will use smaller pots as I believe problems can occur from too greater a volume of unutilised mix in a pot. These bulbs can be remarkably tough and I have successfully grown bulbs in rectangular pots designed to fit in a standard tray. The pot are about 3.3" x 3.7" and around 3.4" deep. Packed in a tray they do seem to behave like a solid block maintaining moderate moisture and temperature levels. I stress that I do not consider this an ideal way of growing these bulbs but when only single bulbs of a given provenance are all that is available there is not a great amount of choice in choosing planting recepticals.
Some Lachenalia do grow in areas that become completely inundated with water at certain times of the year and may survive in a peat based potting mix.
Growing Lachenalia mathewsii
Lachenalia mathewsii is not only one of the easiest lachenalias to grow, it is also free-flowering, each inflorescence lasts for about 3 weeks and it multiplies rapidly. But take note: Lachenalia mathewsii is tender to frost, and is not suitable for permanent outdoor cultivation in regions with a winter minimum of less than -1 oC (30 oF) USDA Zone 10. In cold northern climates, grow Lachenalia mathewsii in a cool greenhouse, in sun or light shade and avoid scorching midday sun.
Grow this lachenalia in a sunny position which has free air circulation. It must have sun to flower well. It is important that the soil be well-drained. Lachenalia mathewsii is not fussy about the pH of the soil and a growing medium of equal parts riversand to loam or fine well-rotted compost (humus) is ideal. Remember to place a layer of stone chips in the base of the container to ensure perfect drainage. The bulbs are fleshy and will rot if over-watered or if planted in poorly drained soil, or if they are watered excessively when dormant. If concerned about drainage of the growing medium, just increase the proportion of riversand to loam/compost. In a garden situation, choose a sunny spot, preferably on slightly sloping ground as the slope maximises water run-off. Drainage in heavy soil can be improved by digging in large quantities of well-decomposed compost (humus) and riversand.
Dormant bulbs should be planted in the autumn, March and April being the best months, as the bulbs become active when the temperatures start to fall at the end of the summer. The roots shoot first, then the leaves. Plant the bulbs at a depth of ±2 cm. Lachenalias enjoy being crowded together and give a better display this way. You should be able to fit twelve to fifteen bulbs in a 200 mm diameter pot. After planting, or when bringing out an undisturbed pot of dormant bulbs, water the pot thoroughly, and then not again until the leaf shoots appear, after which a good soaking once a fortnight is sufficient and better than light waterings more frequently. It is preferable for the soil to be slightly dry than too wet. In the garden, the bed should be watered well in March-April and left alone until the leaves appear and then soaked once every two weeks only if it does not rain.
Lachenalia mathewsii does not require supplementary feeding in order to grow and flower successfully, but it will respond well to judicious feeding. Bone meal is recommended, as is slow-acting organic fertilizer or fertilizers with a high potash but low nitrogen content, all of which can be mixed into the growing medium in moderate to low quantities. A liquid or seaweed based fertilizer with a relatively low nitrogen content can be used at fortnightly intervals.
Towards spring, as the temperatures rise again, the leaves will start to go yellow, which is an indication that the plants are beginning to go dormant. Watering must now be withheld completely and as soon as the leaves have withered, the containers should be placed in a cool dry place to be stored during the summer months. Bulbs in the garden can be lifted at this time and stored in a cool dry place. If left out in the garden, it is best that they receive as little water as possible, but they should be able to survive summer irrigation provided the soil is very well-drained.
Propagation
The focus of research on crop science since 1990 was on indigenous bulbs and in particular on Lachenalia cultivars. Methods for propagation, storage of bulbs, temperature and treatment of bulbs during different times of the growing cycle were researched. The purpose of the work was to optimize flower initiation and manipulation, and flower quality. Although Lachenalia is related to the well-known hyacinths, the temperature treatments used for hyacinths can not be used for lachenalias and research on storage temperature is in progress. Of the various methods tested, propagation of lachenalias proved to be the most successful through tissue culture and leaf cuttings. It was found that the physiological age and the growing stage of mother plants play an important role during bulblet formation on leaf cuttings and on leaf explants in vitro. These methods are currently used at the Institute and by licensees to produce bulblets. These bulblets are grown for two more years before reaching marketable size. Research at ARC-VOPI on cultivation practices of lachenalias proved to be very important for successful introduction of this new crop. These trials included manipulation of the flowering time of Lachenalia by temperature treatments of bulbs during the dormant period and trials to produce pot plants of good quality through the timeous use of growth regulators and temperature treatment. The results of these trials are used in Holland to produce good quality pot plants using bulbs produced in South Africa. Research to increase the yield and quality of bulbs is currently underway. Results of semi-commercial production trials indicated that the cultivars vary with regard to production potential, bulb size distribution, marketable bulb size, etc. Data obtained from these trials have been used to develop a database for production planning. The quality of propagation material has a pronounced effect on the production of vegetatively propagated crops such as bulbous plants, especially as far as the disease status is concerned. Through propagation of disease-free material under isolated conditions and strict sanitation measures, propagation material is supplied to the industry. More than two million Lachenalia bulblets were produced and made available to growers since 1994.
Suitable basic cultural practices need to developed for new crops such as Lachenalia. During the season of 1995 trial were run at Roodeplaat to establish the optimal growing conditions for Lachenalia. An indication of the different levels of nutrition on bulb production, as well as the effect of planting densities and shading levels is discussed.
To establish the nutritional needs, small bulbs of two cultivars were grown hydroponically and treated with four concentrations of a basic nutrition solution as suggested by the Commissie Bemesting Glastuinbouw, Naaldwijk. Collected data include bulb fresh weight and size increase, natural multiplication by offsets and propagation by cuttings, and mineral content of the plants at three stages. The conclusion can be drawn that lower than normal levels of nutrition is preferable to increase multiplication by cuttings, but that a normal level should be used to grow small bulbs to forcing size.
Results of bulbs of the same size and cultivars grown under three different planting densities and shading intensities show that maximum increase in size and weight is achieved by the widest spacing tested and at the highest light intensity tested. Cuttings of plants grown at the lowest light intensity produced more bulblets.
It can be concluded that different growing conditions should be used for multiplication purposes and growing bulblets to forcing size.
seed
Seed is best sown in autumn (March to May) in deep seed trays or pots in a sterilized medium of equal parts fine compost or loam, and riversand. Sow the seed thinly to prevent overcrowding and fungal infection, and to allow sufficient room for each seedling's bulb to develop. Cover with a thin layer of sand, and keep moist and shaded. Germination should occur within five weeks. After germination, the seedlings must be kept moist, not wet, and in a semi-shaded position for their first season. They can be moved into the sun during their second season when some may flower for the first time. They should all flower well in their third season. Seed will remain viable for at least five years at room temperature, even longer if kept refrigerated (not frozen). Lachenalia mathewsii appears not to hybridise when grown nearby other species of Lachenalia.
Crosby suggests that we need to continually replenish stock by growing species from seed but how can we ensure genetic integrity without elaborate cages to stop inter species crossing. It is also easy to grow Lachenalias from seeds but sow the seeds thinly to prevent overcrowding. At a temperature of 18°C (65°F) the seeds germinate in 4 to 5 weeks, and should not be disturbed till the end of the first growing season.
Sow seeds thinly to avoid overcrowding. Keep at a temperature of 65 degrees Fahrenheit. They will germinate in 4 to 5 weeks. Don't disturb the seedlings until they go dormant at the end of their first growing season. Genus restricted to the winter rainfall regions of South Africa. Bright light with good air circulation. Must have media with excellent drainage.
Cuttings & offsets
Through the genus Lachenalia there is quite a considerable range in bulb sizes and in the bulbs propensity to produce offspring. The L. aloides group have probably become popular due to the ease with which most of them produce bulbils. They are thus good for commercial trade allowing a rapid expansion of stock without the fuss of twin scaling or tissue culture and the unreliability of the results coming from seed produced plants. Some species are very shy at producing offset bulbs or dividing. Whether they will divide once a certain size is reached they do usually seem to reproduce well from seed with some producing copious seed.
Lachenalia mathewsii multiplies rapidly by offsets. These are side-bulbs or daughter-bulbs which develop out of the mother-bulb and from which they eventually break away to form separate bulbs. Offsets can be removed during the dormant period and stored until planting-time in autumn. Or a clump can be allowed to develop over a few years, then lifted and divided.
From study of literature a list has been prepared in which the various plant species which can be stimulated to form adventitious buds on isolated leaves are grouped, according to the location type of the 
new-formations
and giving the bibliographical references from which the data have been taken.
Talking of multiplication by division one species that I have found to quite definitely divide is L. unicolor. This species will divide when the parent bulb reaches a certain size and seems to frequently divide into bulbs of approximately equal size numbering from two to a dozen or more.
New bulbs can also be produced by taking leaf cuttings, but only the lower portion of the leaf can be used, as the upper part of the leaf is too narrow. Leaf cuttings must be taken from a healthy plant in active growth. Lachenalia mathewsii produces two leaves, so one entire leaf can be used. It can be cut into two cross-sections, each cutting planted ±1 cm deep in a well-drained rooting medium, e.g. equal parts riversand and vermiculite. The cuttings must be kept shaded and slightly moist. Roots and bulblets will begin to form at the base of cutting in about one month. When the leaf withers, stop watering, remove the little bulblets and store until autumn.
Whether an offset or produced from a leaf-cutting, plants grown from a bulblet should flower in their first season, i.e. a year sooner than a plants grown from seed.
Tissue culture
Lachenalia may be successfully propagated conventionally but with greater yields in vitro. Genotypic variation within and between taxa has troubled both propagation techniques. Further research is required to optimize propagation of Lachenalia in vitro and to ensure its status as a floriculture crop in southern Africa.
Although we do not propagate lachenalias by micro-propagation at Kirstenbosch, the Vegetable and Ornamental Plant Institute, Agricultural Research Council at Roodeplaat has been doing it with great success for years. For more information on this subject, consult the article in the South African Journal of Botany, 1983, 2(3) entitled 'Rapid propagation of Lachenalia hybrids in vitro' by Dorothea D. Nel on page 245-246. Or contact the institute at Private Bag X293, Pretoria 0001.
storage
Remove from garden in summer rainfall areas as bulbs will rot and die during the rainy season. Remove bulbs from soil when leaves become loose on gentle touch. Leave bulbs to dry completely (not in the sun), remove dry leaves and roots and store dry at room temperature (20-25oC), in a well ventilated place. Do not store bulbs in plastic bags. Paper bags or plastic netting is ideal.
Breeding
These hybrids were superior to any of the species as many of them bear many, large, brightly coloured flowers. The result was that growers selected more than 45 of these hybrids in the early eighties for evaluation under commercial conditions. The selections were subsequently registered for plant breeders’ rights. During commercial evaluation in the late eighties and early nineties, significant progress was made in identifying favourable and unfavourable horticultural characteristics of the cultivars. With this knowledge, breeders were able to remove poor cultivars from the variety list and to develop a system for hybrid evaluation and selection that will ensure that only excellent cultivars enter the export market. By the end of 1998, the hybrid evaluation scheme included propagation potential, susceptibility for diseases, time of flowering, uniformity in flowering time, etc. Breeding in the nineties was aimed at developing varieties with improved horticultural characteristics and new flower colours and shapes.
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Basic research in support of the breeding programmes on flower bulbs included studies on cyto-taxonomic aspects and genetic variation, using microscopic and molecular marker techniques, reproduction aspects such as embryogenesis, pollination, etc. Genetic work on Lachenalia is currently done in co-operation with the University of the Free State. Different Lachenalia species have different basic chromosome numbers and in some cases the basic chromosome number varies within certain species. B-chromosomes were identified and described, and polyploidy is relatively common in Lachenalia. Techniques to overcome incompatibility between species were developed and included techniques for embryo rescue, cut-style pollination, pollen storage, etc. |
RAPD (randomly amplified polymorphic DNA) analyses were carried out on 21 accessions of Lachenalia bulbifera (Cyrillo) Engl. Five pre-selected primers produced an average of 88% polymorphisms. Fifteen of the 21 accessions could be identified using the five primers. In a pairwise comparison genetic distance values ranging from 0.11 to 1.08 were obtained. These values reveal a high amount of variation within the species. The genetic distance values within the tetraploid and hexaploid groups on the south coast were low, but values were high between the groups on the south coast and those on the west coast. A dendogram was constructed from the RAPD banding profiles, using UPGM cluster analysis. The dendogram clusters certain accessions together. These clusters are supported by their geographical locality and chromosome data. The hexaploid group, tetraploid group and octoploid group on the south coast are respectively clustered together. It is concluded that RAPDs can be used to assess the genetic variation at an intra-specific level in Lachenalia.
Since mutation is a unicellular event, irradiation of a multicellular meristem results in the so-called diplontic selection. This competition between the mutated cell and the surrounding non-mutated cells is often lost by the mutated cell, causing a low frequency of mutated plants and a narrow mutation spectrum. When a mutated cell survives, chimeras are automatically formed because most apices consist of a number of fairly independent groups of cell layers.
Such an undesirable situation can be improved by growing complete plants from only one cell, resulting in a high frequency of solid, non-chimeral mutants and a wide mutation spectrum.
Many plant species can be stimulated to form adventitious buds on isolated leaves and in a number of cases it has been reported that only one cell was involved.
| The genus Lachenalia consists of approximately 116 species. Many of these species are used in a breeding programme for pot plants at ARC-Roodeplaat, South Africa. Various basic chromosome numbers are present in the genus Lachenalia, i.e. x=5, 6, 7, 8, 9, 10, 11 and 13. Ploidy levels range from diploid to octoploid and polyploidy is present in many species. For breeding purposes it is necessary to know the chromosome number and the genetic diversity within and between species. Species delimitations in the genus are often poor and many specimens are misidentified. Three different subgeneric classification systems have been proposed for the genus. This study evaluates whether the three classification systems are natural. This is done by comparing the system to the basic chromosome number per group and by using sequence data to determine the relationships among the different species. This evaluation clearly indicates that the system proposed by Crosby (1986) is the most natural one and should be expanded to include all species in the genus. | ||
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Applications
They will be indoor forcing bulbs for most of the world, not only because they won't stand much freezing, but because they are winter growers from an area of winter rainfall and summer drought. But they work very well for forcing indoors, being of small size, with flowers that are best appriciated up close. They provide interesting color combinations at a time when there's little color in the garden. Bulbs do great in the garden or in pots on the veranda. Flowers, especially of the yellow varieties, can be used as cut flowers.
Commercialization
Lachenalia is an indigenous bulb growing mainly in the winter rainfall area of South Africa. Unlike other well-known bulbous plants like gladiolus and freesia, commercial lachenalia varieties were not developed by foreign plant breeders. These beautiful plants thus are a true South African product.
The flower industry is constantly looking for new and unique products and this is where the good flower percentage, attractive colours, excellent multiplication, good pot plant qualities, etc, of lachenalias have the potential to establish itself in the overseas markets – especially in the developed countries.
| Each variety is registered for plant breeder’s rights (in Europe) and patents (in USA). All lachenalias are marketed under the trademark Cape Hyacinths. ARC-VOPI is owner of the lachenalia varieties. This means that the Institute developed the varieties and also has the responsibility to establish a market. Lachenalia has been developed for the overseas market since the inauguration of this breeding programme. The local flower industry is too small to develop a product like this, therefore ARC-VOPI appointed agents to assist them with international market development, as well as the selling of bulbs overseas. J.H. van der Vossen is the pot plant grower in the Netherlands. Part of his promotion work in 1999 was to show the lachenalia cultivars at Keukenhof. Cultivar Rupert received the award for the best potted special flowerbulb 1999 on this show. The other lachenalia cultivars also received a first prize on the show. |
Growing this lachenalia in a container is the most rewarding and practical way to cultivate it. It makes an excellent pot subject, and is best in at least 20 to 25 cm diameter pots, or in larger tubs or window boxes, where it can be grown on a sunny balcony, or verandah or in a sunny courtyard. It would also do well in pockets in the rock garden, where it can be displayed to great advantage when planted in groups inter-planted with low-growing annuals like Steirodiscus tagetes, Felicia dubia and Dorotheanthus bellidiformis.
If a pot is taken indoors, e.g. to enjoy the flowers, it should be put in a light airy spot and watered sparingly. The pot should not remain indoors for more than two weeks, as the lower-light indoor conditions promote lanky, weak growth.
Pests & disease
In South Africa where porcupines occur outdoor plantings are liable to be dug up and eaten and if moles are prevalent, particularly the Cape golden mole (runner mole), it is advisable to line the area with wire-mesh or sink a wire basket into the soil as the bulbs can be lifted by the tunnelling activities of the moles.
Lachenalia is susceptible to common bulb diseases, but particularly to virus. Symptoms of virus include mottling of leaves, necrotic spots and stunted growth. There is really no cure for plants that are already infected. Keep your healthy plants away from plants that have been infected with virus and remove and destroy plants with symptoms as soon as possible. Virus is transmitted from diseased to healthy plants by means of aphids and offsets.
Virus seems to be quite a problem in the genus particularly as it is not always immediately visible. Crosby in The Plantsman Vol8(3) 1986 refers to the hyacinth mosaic virus and the ornithogalum mosaic virus. He also writes "I strongly suspect that there are other weaker viruses, showing no clear symptoms, which are widespread in stock of Lachenalia and other bulbs." He
suggests that seedling bulbs are most vigorous but that the plants loose vigour over a few seasons until they are no better than the standard sort.
