There are two primary methods of propagating sempervivum: vegetative (daughter plants) and generative, which is done through seeds. I’ve personally experimented with both of these methods and would like to share my experiences with you, along with some helpful tips.
Once the plant has taken root, it starts producing new baby rosettes around itself. The number of daughter plants that develop varies depending on the species and varieties, ranging from 2-3 to as many as 10 new plants.
The formation of young plants differs among various sempervivum species. In most Sempervivum varieties, they sprout from horizontal shoots, either at a distance from or close to the parent plant.
In the case of sempervivum globiferum, new rosettes actually form directly on the parent plant and, once they mature, they detach and root themselves.
Sempervivum heuffelii, on the other hand, follows a more unique method of reproduction. Its parent rosette divides into 3-4 new rosettes, and to obtain new plants, you need to separate them using a knife.
Tools for propagation
To propagate Sempervivum, you will require the following items:
- A pot (if you are propagating these plants in a container).
- Substrate (the soil should be mixed with an equal amount of sand).
- A garden knife.
- A shading grid.
Before you separate the young plants, make sure to choose the largest in terms of diameter and the healthiest ones.
Additionally, keep in mind that the propagation process is highly influenced by the season and the size of the Sempervivum plant.
Best time for propagation
It’s best to transplant young rosettes during the spring or late summer when the sun is not too intense. I would advise against propagating Sempervivum during hot weather. It’s also not feasible to separate these plants during the winter months.
Season | dwarf varieties | medium varieties | large varieties |
Spring | yes | yes | yes |
Summer | no | yes | yes |
Autumn | yes | yes | yes |
Winter | no | no | no |
Wait until the young rosettes reach a diameter of 0.5-1 inch before transplanting them. If you attempt to divide plants that are smaller than half an inch, they may not establish roots and could perish.
6 Steps of Sempervivum Propagation
1. Choose healthy and juicy rosettes
To ensure successful propagation, opt for young, larger plants that have already started developing roots. These plants will establish themselves more quickly in their new location and exhibit stronger growth.
If you separate plants that are too small from the parent plant, it may take up to a year for them to root, and there’s a risk of them not surviving. It’s advisable to select plants that are at least one year old for the best results.
2. Separate the young plants from the mother plant
When separating the young rosettes from the parent plant, you can use a garden knife if needed. Be careful not to harm the roots that have already developed in these young plants.
Avoid rinsing the roots with water, as it can complicate the rooting process. A bit of soil on the roots is perfectly fine; there’s no need to remove it.
If the young plant has dry leaves, delicately take them off. Make sure not to damage the healthy, living leaves, as this can potentially lead to disease development.
3. Prepare a place
Select a suitable spot for rooting. Prepare the planting area by mixing garden soil and sand in a 1:1 ratio, then fill the designated planting area with this mixture.
Now, gently place the sempervivum roots into the soil, ensuring that the rosette remains above the ground level. Fill the area around the roots with the prepared soil mixture. Make sure to position the rosettes at an adequate distance from each other, with at least 2 inches of space between them.
4. Shade plants
If you’re propagating a dwarf variety, it will require some shade.
To provide shade, insert two sticks into the ground and stretch a shade net between them. Alternatively, you can position a pot with other plants in front of the young Hens and Chicks.
This shade is necessary for a brief period, typically 1-2 weeks. However, if there is minimal sunlight or the weather is cloudy during the rooting process, you may not need shade at all.
5. Water plants
Take great care when watering the separated plants. Begin watering them 3-4 days after planting; avoid immediate watering right after planting!
When you water, use a modest amount of water initially, merely dampening the Sempervivum. Then, gradually increase the water volume. Allow the soil to dry out between watering sessions.
Remember, watering is only essential if there has been no rain; there’s no need to water the Sempervivum when it’s raining.
6. Give a small amount of fertilizer
Around 30-40 days after separation, your Sempervivum should have established roots in their new location. At this point, you can apply a modest amount of fertilizer to promote their growth and development. To achieve this, opt for slow-release fertilizers as they provide young plants with the necessary nutrients more effectively.
It’s important to use fertilizer sparingly. Sempervivum naturally produces many vitamins and elements, requiring minimal additional nutrients. A few pellets placed under each rosette will suffice.
How fast do hens and chicks spread?
The plant begins with a primary rosette, known as the ‘mother’ or ‘hen’. As it matures, it produces numerous smaller rosettes, referred to as ‘chicks’, which are connected to the mother plant via lateral roots. This results in the formation of a tightly-packed group of rosettes. Over a single growing season, this colony typically expands to cover an area of about 2 to 3 feet.
Propagation sempervivum by seeds
This method of reproduction is undoubtedly the most demanding and meticulous, but it can yield fascinating outcomes. Sempervivum hybridizes exceptionally well, allowing you to obtain plants with distinctive decorative attributes.
The flowering process typically commences in the third or fourth year of a plant’s life. The Sempervivum rosette transforms into a stem, ranging from 4 to 15 inches in height, at the top of which inflorescences develop. Sempervivum can bloom anytime from May to September. The period from the onset of stem formation to seed maturation can span approximately two months.
How to collect seeds from Hens and Chicks?
To gather seeds, trim the inflorescence, put it in a plastic tray, and leave it in a dark, dry location to dry.
Since the seeds are quite small, separating them can be challenging. Instead you need to grind the dried inflorescences, including the seeds, and then sow the resulting mixture into the soil.
Sowing
Spring is the ideal season for seed sowing.
To sow the seeds, use plastic trays that are at least 4 inches deep and equipped with drainage holes at the bottom. Fill the container to about two-thirds with a mixture of garden soil and sand in a 1:1 ratio. On top, add a layer of clean peat or seedling substrate.
Now, simply scatter the seeds on the surface; there’s no need to cover them with soil. Moisten the tray’s surface with water and either place it in a greenhouse or cover it with a transparent lid to maintain the necessary humidity.
Approximately a week later, young seedlings will emerge. It’s crucial to maintain a consistent temperature of around 68°F and provide diffuse sunlight during this period. Additionally, make sure to ventilate the young plants once a day, and keep the soil consistently slightly moist.
Once the young plants reach a size of 0.5 inches, they can be exposed to full sunlight. After about a month, they can be separated.