How to Grow Sempervivum arachnoideum? A Complete Guide to the Latest Cultivation Methods
Sempervivum arachnoideum is a succulent plant of the genus Sempervivum in the Crassulaceae family, characterized by the natural webbing that clings to the leaf tips. Individual plants of this species vary considerably, with each one differing in diameter and in how dense the webbing is, and it readily crossbreeds naturally with other varieties of Sempervivum. It has high ornamental value, so let us take a look together at how to grow Sempervivum arachnoideum!
Growth Habits of Sempervivum arachnoideum
Sempervivum arachnoideum is distributed in southwestern Europe and can now be cultivated in many places around the world. It grows quickly and readily forms clusters, prefers cool conditions and a sunny, well-lit environment, dislikes damp heat, is cold-hardy, and goes dormant in summer when temperatures are high, with spring and autumn being its growing seasons. In soil with good drainage, full sunlight and a large temperature difference (or low temperatures), the undersides of the leaves turn red or purple. It dies after flowering, so the flowering period can be used for pollination or division.
Propagation Methods for Sempervivum arachnoideum
Propagation methods for Sempervivum arachnoideum include sowing seeds, division and beheading cuttings. The simplest division method is generally used: remove the small offsets, insert them into slightly moist soil, and wait for them to root in a cool, ventilated place. The soil used for cuttings can be the same as that used for mature plants, but this species cannot be propagated by leaf cuttings.
Cultivation Methods for Sempervivum arachnoideum
1. Soil: For Sempervivum arachnoideum, choose a soil mix of peat mixed with perlite and coal cinder, roughly in a 1:1:1 ratio. To separate the plant from contact with the soil surface and to improve aeration, you can spread clean granular river sand on top, with a particle size of 3 to 5 mm.
2. Watering: Sempervivum arachnoideum generally should only be watered thoroughly once the potting soil has dried out completely; if it is not dry, do not water. When watering normally, try to pour the water into the soil and avoid spraying the plant directly, as the “webbing” may come off when it gets wet. Do not water into the center of the rosette, as it easily rots.
3. Summer: Summer is the dormant period for Sempervivum arachnoideum. It should be shaded appropriately and ventilation strengthened. Stop watering when temperatures are above 35°C, otherwise it will very easily rot. Water 3 to 4 times a month, giving a small amount of water around the edge of the pot each time, to keep the plant from drying out and shriveling due to excessive dryness.
4. Winter: When growing Sempervivum arachnoideum in winter, watering should gradually be stopped once temperatures fall below 3°C. Keeping the potting soil dry at around 0°C is basically enough for it to survive the winter safely; try to keep it no lower than minus 5°C.
5. Pests: The most common pest of Sempervivum arachnoideum is root mealybug. You can bury carbofuran or soil insecticide in the soil for prevention, spray abamectin once each at the start of summer and the start of winter, or use Huahuashen as a soil drench for treatment. Growing it outdoors in the open can also prevent ordinary scale insects to some degree.
6. Diseases: The main disease of Sempervivum arachnoideum is black rot. If the roots or lower leaves show blackening, you can dig the plant out early, clean away the rotted roots and leaves, and if necessary cut off the rotted stem and place it on dry soil to re-root. However, if the center of the rosette rots, the chances of survival are basically very slim. Once black rot occurs, the diseased plant should be dug out or isolated as soon as possible to prevent the bacteria from spreading.