Selenicereus grandiflora - Queen of the night
One of the questions is : how do I get a flower on this plants ?
My experience in Belgium I can describe, how this genus is doing it in the nature I do not know.
In the beginning of the 90 years I had the same question. A certain mister Haenen in Germany told me this plant needs a large amount of soil, heat, light and space. I think this is(are) the key(s).
My plants are installed in a veranda. In the winter, from the beginning of october until the middle of april, this area is kept dry, cold at night (minimum to 4 degrees) and as warm as posible over day (the door is only opnened at more than 25 degrees. In april-mai we are watering on the soil. In the morning, on sunny days, we vaporise warm water (more than 40 degrees). From june we are watering one time a week in the evening and that with a large spray and during several minutes.
When you look to the stems, you will see there are air-roots. The most of Selenicerei, Eriocerei, Nyctocerei need a good foot but are so long that water has been taken from the air. So it is good they become the water on the stems in stead of on the soil.
Let this plants climb very high in the greenhouse or the veranda. At the top the temperature is at a maximum over day, and at night at a minimum : very large differences in day-night temperatures.
From mai we have no more night-frost in Belgium and from that moment we let the veranda entirely opened : that means fresh air day and night. A standing heat is deadly !
I had some plants outside. They are all lost. In our country we have to much rain. So give your plants water in one our two weeks from mai until september and only when the weather is warm.
To have a good result this plants need light. Let them only grow when there is light anough. From the equator to Spain-Mexico they may grow the whole year with a period of rest from december trough february. 60 degrees north (or south) will be a maximum and only june until the end of august this genus may grow, perhaps not long enough to become flowers.
Selenicerei are marvelous, but they are not alone. A lot of Echinopsis are doing well when you place them outside in rain and wind from the end of april. Eriocereus jusbertii, E. bonplandtii, Nyctocereus serpentinus give each year a lot of flowers. Do not forget all the Trichocereus species : very large white flowers during 2 or more days depending the weather is heat or cool.
Of course there so many other species, enjoi them all..
Jef Keymeulen, Cactusclub 'AYLOSTERA' - Aalst vzw
Updated : 2000.08.03-02:38