SUMMARY.
Penrock Plants specialises in the propagation of geophytic and succulent pelargoniums, with specific reference to species in the Section Hoarea of the Genus Pelargonium. The plants are grown from seeds set by documented mother stock. In most instances seeds are collected from quite a range of mother stock in the case of specific species. The nursery thus represents most of the variation in size and flower colour to be found in the different species.

The types of plants offered in the nursery are discussed in this newsletter and a library of colour slides of the plants is displayed. The slides feature many of the more spectacular stocks in the nursery.

NEWSLETTER.
There is a worldwide interest in the geophytic and succulent pelargoniums found in South Africa and south western Namibia. Most of them are found in the winter rainfall Cape Provinces and the autumn and winter rainfall corner of south western Namibia.

The ornamental leaves of Pelargonium radicatum photographed in the middle of the winter growing season.

Some of the species are well known in cultivation such as Pelargonium carnosum and Pelargonium incrassatum. Others such as the rare Pelargonium heterophyllum are little known and rarely available in the trade.

New pelargoniums are regularly found and several unusual species with beautiful flowers in the Section Hoarea await formal description.

The main factor limiting the production of geophytic and succulent pelargoniums is the production of seeds. Several species produce good amounts of seed in cultivation. In the case of others the seed set is very limited despite careful hand pollination.

Pelargonium radicatum produces massed umbels of flowers as the plants enter dormancy in early summer.

PRODUCTION OF PELARGONIUMS FROM SEED IN THE NURSERY.
Penrock Plants produces pelargoniums in one large greenhouse with a clear polycarbonate roof. The sides of the greenhouse are open to permit good amounts of free air circulation. Free air circulation is required in order to keep plants free of pests and to aid the ripening of pollen on the flowers in the spring and summer.

Johannesburg where the nursery is situated has an ideal climate for producing pelargoniums from the winter rainfall region. The days in the winter, when the plants are in active growth, are sunny and mild with virtually no cloud cover for five months, May-September. The night temperatures are mostly from -1 degree to 3 degrees centigrade.

Seeds are sown in May which is usually the best month for germination. It generally takes 7 - 21 days for seeds to sprout and with some species seeds only germinate the following autumn or early winter. The young plants are watered throughout the winter months until the leaves die back in late August and September, as the temperatures warm with the start of spring.

The tubers are kept bone dry for the duration of the summer and watering is resumed again in early May as the days shorten and the temperatures drop.

Most Section Hoarea pelargoniums reach flowering size at the end of their second growing season. In the case of some succulent pelargoniums this is much longer - up to 5 years in the case of Pelargonium paniculatum.

Pelargonium heterophyllum has some of the most beautiful flowers of all the Section Hoarea Pelargoniums.

Plants are lifted and exported in the early autumn, late April and May, or else at the end of their growing season just before dormancy, between late August and early October.

PRODUCTION OF PELARGONIUM SEED.
Pelargoniums are carefully pollinated in the nursery with the use of cotton buds. The seed set of many species in cultivation is poor without hand pollination. Some seeds are offered for sale by Penrock Seeds and the balance is used for propagation in the nursery. The seed set in different plants varies greatly from one year to the next. Little pollen ripens during cold weather which often implies no seed set for some species which flower during cold conditions in spring and early summer.

Some species are difficult to pollinate with small well concealed anthers such as Pelargonium heterophyllum.

The pelargonium seed list is updated when the bulk of the seeds of most species has been set, in early November. Seed produced by the autumn flowering species is normally listed in April shortly after the close of the seeding season for these species.

INTERESTING AND ATTRACTIVE PLANTS OFFERED BY THE NURSERY.
Some of the more interesting plants available in the nursery are discussed below, with specific reference to cultivars with attractive flowers, undescribed species new to cultivation and rarities.

Pelargonium ochroleucum has a unique combination of yellow and white flower petals.

UNDESCRIBED SECTION HOREA SPECIES AND THOSE NEW TO CULTIVATION.
Several unusual attractive Section Hoarea plants are offered by the nursery. They are all rare in nature and found in small distribution ranges, mostly in the Western Cape Province.

Pelargonium Section Horea nova species from the mountains near Villiersdorp grows in fynbos. It has dense pinnately compound foliage in winter and very large ornamental cream flowers at the height of summer, in early January. At this time the tubers are fully dormant. To date this species is only known from the summit of one mountain.

Pelargonium Section Hoarea nova species Nardouwsberg near Clanwilliam. This unusual plant has cloverlike foliage in winter held on the ends of curved stems. The white flowers with a distinctive chocolate brown blotch appear at the height of summer and in early autumn from January to March.

Pelargonium Section Hoarea nova species Klein Roggeveldberge. One of the most ornamental species found in recent years is confined, apparently, to a small area in the foothills of the Klein Roggeveldberge. The plants have densely pubescent compound leaves in winter. The congested umbels of yellow flowers with brown feather markings follow in early summer as the leaves start to wither. This plant has the unique characteristic of having strongly aromatic flowers and not foliage. The foliage of most pelargoniums is aromatic but not the flowers.

Near Kamieskroon in the Western Cape is another peculiar undescribed species in the Section Hoarea. It has leaves quite unlike any other pelargonium resembling a maidenhair fern. The leaves are produced in winter and when they wither in early summer the tubers sprout massed umbels of yellow to cream flowers with long upper and lower petals bearing crimson feather markings.

The smallest of the currently undescribed Section Hoarea pelargoniums is found near Robertson growing on gently undulating slopes. The rosette of simple leaves in winter is only a few centimetres wide. Massed umbels of creamy yellow flowers with broad petals bearing blood red blotches are produced in the early summer. This species is quite often found growing together with Pelargonium violiflorum.

CULTIVARS PRODUCED IN THE NURSERY.
Several attractive cultivars have been bred in the nursery. Included amongst these are the Pelargonium incrassatum. These have flowers that range in colour from pale salmon to dark pink. In addition the most widespread colour in nature, a deep cerise has also formed the basis of several selections. The cultivars have very large umbels of dark and pale cerise flowers. One of them has flowers which are a rich royal purple.

All the P. incrassatum cultivars have been bred for their floriferous habit and long flowering period which lasts from August to late September under cultivated conditions in Johannesburg.

Selections of the highly ornamental Pelargonium oblogatum have also been made. These have large umbels of deep yellow flowers with prominent crimson feather markings. Selections have also been made in favour of plants with large partly exposed tubers and leaves. Selected clones of Pelargonium sericifolium have been bred for their dark flower colours and extended flowering periods.

RARETIES GROWN IN THE NURSERY.
One of the objectives of the nursery is to make available pelargoniums that are rare in nature. Some of these could enter the ranks of extinct plants during the course of this century. Several pelargoniums have become rare owing to habitat destruction and degradation.

Pelargonium heterophyllum is one of South Africa's rarest plants. This species is narrowly endemic to the Darling area of the Western Cape. Most of its habitat has been destroyed by wheat fields and few viable populations are currently known. The tubers produce particularly ornamental and beautiful flowers as the leaves start to wither in the early summer. Little seed is produced in cultivation but that which is set is used to propagate plants for collectors and the nursery trade.

The flowers of Pelargonium curviandrum are amongst the most attractive in the Genus Pelargonium.

Pelargonium hirtipetalum is one of the most attractive of the Section Hoarea species and is found around Springbok in Northern Namaqualand. The nursery is offering limited numbers of this plant in 2004.

The monopodial form of Pelargonium hystrix is found in the Ceres Karoo and the Matjiesfontein Karoo. The plants from the Ceres Karoo has very long stipules which harden to form prominent white spikes. These plants are very localised and are confined only to the extreme south west corner of the Ceres Karoo. The nursery propagates Pelargonium hystrix whenever sufficient seed is available. The seed set is very erratic, and in some years no seeds are produced.

Pelargonium ochroleucum is one of the very rare species in the Section Hoarea. It is only known from one farm at present in the Lake Mentz area north of Port Elizabeth in the Eastern Cape. The plants grow mostly in the shelter of low karooid scrub where they escape trampling by grazing sheep. The flowers appear in the early summer as the leaves wither. They are most unusual and striking with a combination of white and lemon yellow petals. The nursery has been making small numbers of these available in recent years.

Pelargonium radicatum is a particularly ornamental and attractive species. It has been infrequently and sparsely recorded from the Western Cape to northern Namaqualand. The only recent records are from two localities in mountainous terrain north west of Springbok.

The tubers sprout grey spear shaped leaves in the winter months which connive to form an attractive rosette. The umbels produced in early summer contain numerous yellow flowers with distinctive pink markings. The old leaves are persistent and their olive red brown colour contrasts attractively with the current season's grey foliage.

NURSERIES WHICH STOCK SELDOM OFFERED SUCCULENT AND TUBEROUS PELARGONIUMS IN SOUTH AFRICA.
Very few nurseries carry a range of succulent and tuberous pelargoniums in South Africa. These used to be available at the South African Pelargonium & Geranium Society shows. The Society will be closed as from October this year. The range of species formerly available at the shows through Penrock Plants will now be available from Random Harvest Nursery near Johannesburg. Linda de Luca, the proprietor of the nursery, will have a range of plants available for South African enthusiasts from July 2004. Plants may be purchased from Random Harvest Nursery and will in due course be available within South Africa via a mail order service.

Please contact Linda de Luca if you would like details of the plants which she has available. Linda may be contacted at telephone number (011) 957-2758 or by email at linda@rhn.co.za

SEED AND PLANT CATALOGUES.
Seed and plant catalogues will be emailed on request. Penrock Seeds and Penrock Plants have wholesale seed and plant catalogues for the nursery and also retail seed and plant catalogues. Interested parties should inquire via our email address.

SLIDE LIBRARY.
A number of slides featuring some of the succulent and tuberous pelargoniums in the nursery are featured below in the slide library.