July 2012


This rare species comes from South-Africa, to be more precise, from the mouth of St. John’s River in Natal. It is a tuberous-rooted species and produces annual growth. It can take some frost as long as it is covered over in winter. It can also be grown in a cool greenhouse, but will get straggly if it gets too hot. The risk of spider mite will also be greater if the temperatures gets too high. It will flower from July onwards, no matter where it is grown. The colour of the flower varies from pinkish-white to pink; the most common colour in circulation is the one you see in my picture below.
The plant is propagated either by seed or cuttings; the latter being the most common means of reproduction as there is little seed available, because you need two clones to get seed. The cuttings of this species will produce a tuber unlike, for instance, impatiens tuberosa which does not. The plants grow to about 50-100 cm high in pots and topping will force it to produce side shoots for a nice bushy plant. In the wild, it can grow to 2 metres high.

 

Impatiens flanaganae

Impatiens flanaganae

This plant is also known as Stultitia conjuncta, but in 1978 it was moved to Orbeanthus. Recently, Peter Bruyns, one of the top Stapelia people, has placed it in Orbea, but there is a lot of movement in the naming of Stapelias, so it is entirely possible that it will be moved back to Orbeanthus. This genus contains only two species; the other one being Orbeanthus hardyi.
It is not a common plant in cultivation, but is very suitable for a hanging pot; the stems can grow up to 50 cm in length and are greyish green mottled with darker green. The flowers are cup-shaped and look similar to those of Hoya archboldiana, the colour being white with a red centre. The flowers are produced singly or in pairs, mainly in the summer.
It requires a well-drained soil, preferably mixed with grit. Propagation is by seed or cuttings. Cuttings need to dry for a couple of days before being put in the soil to avoid rot, as is the case with most succulents. Bottom-heat is preferred to speed up rooting. The plants can be grown either in full sun or shade, but you will get more mottling on the stem if they are kept in the sun.

Orbeanthus conjunctus

Orbeanthus conjunctus

This tropical asclepiad originates from South-America and is now widespread in most (sub-)tropical regions of the world, such as Spain. It is both drought-tolerant and the opposite; it can take plenty of rain. It is a climbing plant that can grow to up to 5-10 metres high. In some countries it is now considered to be a weed, but it is nevertheless a highly ornamental plant, producing pink-striped white flowered. The flowers are scented all day, unlike some asclepiads, among them some hoyas for instance, which are only scented at night. The plants are mainly moth-pollinated, certainly in their country in origin, but in other countries where they have established and the correct type of moth is not present, the pollination is done by bees. Araujias are known as the cruel plant, because if the wrong type of moth (i.e. too small a moth) tries to pollinate the flower, its tongue will get stuck in the pollination system, and unable to escape, it will die. Bees and larger moths do not get stuck because they are heavy enough to pull free. Seedpods produce up to a few hundred seeds per pod. The seed is carried on the wind by small parachutes, similar to thistles.
Araujias are close relatives of the Dregea from China, of the Periploca from the Mediterranean and of the Stephanotis from Madagascar and are very easy to grow as houseplants, being able to grow in shade or sun, and not fussy as regards soil. The only limiting factor is frost. The flowering period is summer. Propagation is mainly from seed, but cuttings are also possible.

Araujia sericifera

Araujia sericifera


Araujia sericifera

Araujia sericifera