||Inch-by-inch plant, Holiday cactus
Schlumbergera is a genus of epiphytic (lives on trees) cactus that comes from the jungles of Brazil.
Like most cacti, it is leafless and its flatten stems have taken over the responsibility of photosynthesis, producing food for the plant from light.
The Christmas cactus is so named because it flowers during early Winter and in the Northern hemisphere, this coincides with Christmas.
In New Zealand, this cactus flowers in June, providing a splash of colour when needed most.
A related species, the Thanksgiving cactus flowers a month earlier, its flowers fading just as the Christmas cactus' are starting to open.
The flower is made up of whorls of petals, the varying length base fused to form a tube.
The pollen is cream, and the brightly coloured stamen is usually of a contrasting colour.
A lot of breeding work has been done on Schlumbergera, and as a result, a wide variety of colours are available today, from white to red, to purple and yellow, and all the colours in between.
Epiphytic cacti will grow in most commercial potting mix, as long as adequate drainage is provided.
The main growing season is in the Summer, but it requires a period of long nights (at least 13 hours of darkness) for a couple of months during the Autumn to initiate flower buds.
The most common reason for these cactus to fail to flower is because they are kept indoors, where home lighting at night effectively shortens its nights.
When the cactus is in bud, do not move it.
Any change in temperature or light orientation can cause the buds to drop.
This is also the time to adequately water the cactus as it needs water for the buds to grow to flowering size.
Inadequate water will cause stunted buds which eventually drop off.
The other time when this cactus requires water is during its growing season in the Summer.
When watering, ensure that the pot is thoroughly saturated and allow the excess water to drain away.
Never sit the pot in a saucer of water! Having said that, do not let the mix completely dry out for too long.
Jungle cacti, unlike desert cacti, do not have much water storage, and will start to shrivel when stressed.
Reduce water after flowering.
Light shade is best of this cactus.
Bright sun will yellow its stems but leave the plant in dark shade and it will not flower.
The ideal Summer temperature is around 15° at night and 25° during the day.
Keep away from frosts in the Winter.