(Second of two parts)
(This week Succulentophile gives way to an article by Peter A. Bangayan.)
Succulent plants need regular watering during their growing period to grow well. One of the many questions asked by beginners is “How often do I water my plants?” It usually takes a bit of practice and observation to know when the plants need to be watered. The rule of thumb is to water when the soil mixture is almost dry and to water thoroughly. I do not advise letting the soil mix go bone-dry because in many instances the roots of the plant will die and the plant will most likely rot when subsequently watered because they can no longer absorb water and nutrients from the soil mixture. A number of plants have their active and resting period. Most cacti begin to grow actively during summer and slow down during the winter months while some leafy succulents go dormant (lose their leaves to conserve water) during the summer and grow during the winter. Water plants more often during the active growing period and water-less during the resting period. For the beginner, I would also recommend clay pots rather than plastic pots because clay pots are porous and dry much faster so that the chances of overwatering and rot are minimized. Another question most often asked by beginners is: “Do I fertilize my plants? And: “How often should I fertilize or feed my plants? If a plant is newly potted, the compost part of the soil mixture will take care of the plant’s nutritional needs but after several months of growth the nutritional portion of the soil mixture becomes depleted and the plants can then be fed with a dilute fertilizer during their active growing period. The recommended fertilizer should contain less nitrogen (N) and higher phosphorous (P) and potassium (K) content plus micronutrients.
Many Euphorbias from tropical Africa, India, and Madagascar such as E. antiquorum, E. lactea, E. grandicornis, E.milli, E. stenoclada, E. tirucallii, etc. can be grown out in the garden without protection from the elements. The small branching Euphorbias such as E. greenwayii, E. gemmea, E. marsabitensis are also very easy to grow but need a little protection from the rain, especially during monsoon season. Leafy Euphorbias from Madagascar such as E. aureoviridiflora, E. leuconeura, and E. viguieri as well as the dwarf E. cylindrica, E. capsaintmariensis and E. decaryi do very well here in the tropics. The South Africa medusa head Euphorbias, such as E. brevirama, E. decepta, E. esculenta and others, do not adapt well to our tropical climate.
Most Agaves like A. americana, A. angustifolia, A. lechuguilla, A. sisalana, and A desmettiana can also be grown out in the garden while the smaller and more sensitive species of agaves such as A. arizonica, A. ferdinandi regis, A. filifera, A. impressa, A. potatorum, A. pygmeae, A. striata, A. stricta, and A. victoria-reginae need some protection from heavy and continuous rains. The related genus of Sansevieria, which has become quite popular lately with some collectors, comes from tropical Africa and India. Most species grow well without protection from the elements. In fact, Sansevierias seem to thrive in our hot and humid climate.
Adenium, commonly called “desert rose” or locally known as Bangkok calachuchi, tolerates overwatering and is usually grown exposed to the elements here in our country. The more sensitive varieties and cultivars are usually grafted onto A. obesum. Another related plant, which is easy to grow is Pachypodium lamerei. Pachypodiums, such as P. lamerei, P. geayi, P. saudersii, P. lealii, P. sofiense, and P. rutenbergianum can be grown outside in the garden exposed to the elements if planted in a well-draining coarse medium. Other smaller pachypodiums, which are easy to grow but need some protection from the rains, are P. ambongense, P. baronii, P. decaryi, P. horombense, P. rosulatum.
Many Asclepiads, such as Huernias and Stapelia, are commonly available and easy to grow. During the hot summer months, they grow quite fast if given enough water and fertilizer. During cooler weather, the growth usually slows down and plants should not be overwatered. Stapelia gigantea has plate-sized, star-shaped flowers that smell of carrion which attracts flies, the main pollinator of most stapelias. Vine-like Hoyas with their attractive globe-like flowers also belong to the Asclepiad family and are very easy to grow; many of the species are from the Philippines and tropical Asia. In the wild, Hoyas usually grow on tree trunks and therefore need semi-shade conditions.
Collecting cacti and succulents is interesting and can become a lifelong hobby. The unusual forms of these plants will always fascinate and intrigue the curious mind.