How to plant, grow and look after your Sempervivum plants

A complete guide for the propagation, pruning and general plant-care for all types of Sempervivum, Hens and Chicks.

• Botanical name: Sempervivum
• Common names: Hens and Chicks, Houseleeks, Liverforever, Old Man and Woman, Welcome-home-husband-however-drunk-you-be (and loads more!)
• Family: Crassulaceae
• Type: Evergreen succulent
• Flower colour: Pink or pale yellow
• Height: Max. 10cm
• Spread: Max. 50cm

Growing Conditions

• Light: Full sun
• Water: Little
• Temperature: Frost tolerant. Some species can survive a minimum of -20ºC
• Soil: Free-draining, sandy or loamy
• Aspect: North, south, east or west-facing

What are houseleeks?

The Sempervivum or houseleek is an intriguing, low-growing, mat-forming, succulent plant. It is evergreen and forms rosette-shaped plants in greens, reds and yellow – almost resembling little roses. It can also produce flower spikes in pinks or pale yellow. It is an incredibly hardy plant - surviving most temperatures in the UK - is easy to grow and comes in a wide range of different species, varieties and cultivars. It is a wonderful little plant all round.

Perhaps, the most common species is the Sempervivum tectorum (Roof Houseleek), which is native to southern Europe. It forms large rosettes in green with purpley-red tips. As with all Sempervivums, it reproduces vegetatively when the main rosette, known as the “hen”, produces tiny, offset rosettes known as “chicks” (hence the common name, Hens and Chicks).

This care guide can be applied to all Sempervivum species including Sempervivum arachnoideum, Sempervivum calcareum and Sempervivum wulfenii.

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In what site and situation should I plant my Sempervivum?

Sempervivum grow most happily outdoors (in and out of protection) in the UK, although some people may find theirs grow successfully indoors too. The most important factors to consider when planting your Sempervivum are light-levels, moisture-levels and ventilation.

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How much water should I give my houseleeks?

Sempervivum require very little water – as with most succulent plants. They dislike sitting in waterlogged soil, which can cause root rot.

Water very occasionally, when the soil is dry. Again, as with most succulents, one generous watering once in a while is better than lots of light waterings. Upon watering you potted houseleeks, completely soak the soil until it runs out the holes in the base. Don’t water it again until it's completely dried out again – this may be a couple of weeks, or more in the winter months.

To check the moisture levels in your soil, you can poke a finger into the soil of your potted plant – water it well, if it is dry, and if it feels wet, wait for a few days before checking again.

If your plant ever starts to actually look a bit dry and you haven’t checked the soil in a while, go ahead and check (succulents should look "succulent" after all). If the soil feels dry, give it a good drink.

Generally the watering requirements for all succulents are highest in the spring and summer. In autumn and through the winter, you will need to start reducing the amount of times you water your Sempervivum plants to about once a month. If you aren’t sure, just keep checking how moist the soil feels – this is the easiest way.

There is no need to give plants planted in open-ground, outdoors any additional water. Sempervivums are so incredibly drought tolerant that they can stand any very dry weather that we have in the UK.

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What soil do Sempervivums prefer?

Houseleeks thrive in free-draining, nutrient-low soils. Outdoors, in open ground, poor, sandy soils are perfect. If you have a very heavy, clay soil, you can work in a commercial soil-improver, grit or pea-sized gravel – to lighten it and to improve the drainage. Be mindful when incorporating too much organic matter, to loosen the structure of your soil, that you don’t add anything too rich. Something like manure is too rich as it contains too many nutrients, even when well rotted.

If you are growing your Sempervivums in containers, apply the same rules you would for most succulent plants, and choose a well-draining compost that isn’t too fertile. A soil with a neutral pH is preferred.

Specialist cacti and succulent mixes are perfect – either “off the shelf” or homemade – with just the right soil particle to air ratio. Mix sand, perlite and soil – 1 part sand : 1.5 parts perlite : 1.5 parts soil.

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Do Sempervivum plants need feeding?

It is not necessary to give Sempervivum any supplementary feed as they tend to do really well in “poor” soil. If you think your plant would benefit from feeding, feed it in spring at the start of its growing season. Choose a controlled-release fertiliser and feed just once a year. Be careful not to overfeed your houseleeks, as nutrient-low soils promote far better leaf colour and result in sturdy, firmer rosettes.

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Why did my flowering houseleek die?

It is a completely natural process that a Sempervivum plant will die after it has flowered. When a houseleek is on its way to flowering, you will see it stretching up and growing taller. Buds will form at the end of the flowering stem before opening to reveal pink or pale yellow, star-shaped blooms. Once flowering has ended, the plant has completed its life lifecycle so it dies, by which time it has usually produced many offsets (baby “chicks”) which will continue to grow.

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How do I repot a Sempervivum?

The best time to replant your houseleek is as it starts its growing at the beginning of spring. Only take a very young plant out of it’s existing pot when the soil is fully dry.

• Prepare a suitable container with drainage holes, and part fill with an appropriate potting mix (described above).
• Gently knock your plant out of its container, and tap the soil away from the roots (removing any rotted or dead ones as you go).
• Place your plant in the new pot and backfill with your potting compost -
• Spread the roots out as you plant.
• Cover the plant right up to its crown and compress the soil to make sure its firm in the pot.
• Be careful not to plant it too deeply.
• Top dress with horticultural grit or small gravel, making sure to distribute the grit right up underneath the base of the rosette. This will protect the crown of the plant and stop it from sitting on wet soil – it also looks really attractive, especially around container-grown plants.
• Don’t water the plant for approximately one week to prevent root rot. After one week, water sparingly from then on, as described earlier.

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Do I need to prune my houseleek?

No. Sempervivum species require no pruning, but you should cut off spent flower spikes and carefully remove dried, damaged and dead leaves.

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How should I propagate Sempervivum succulents?

It’s so easy and fun to propagate these little succulents – which ultimately means that you can very easily grow new plants, for completely free.

Sempervivum’s natural growth habit and way of vegetatively reproducing lends itself to effective propagation, and give it one of its common names, “Hens and Chicks”. This name refers to the way that the mother hen produces an offset chick from little, horizontal stems (stolons) all around it. These offsets can be separated and divided for very easy propagation.

Alternatively, you can leave the chicks so that they remain attached to the hen. They will naturally root down into the soil and in time, produce their own chick offsets – eventually filling up all the growing space and forming a clumping mat of rosettes. This will create an attractive, easy to maintain landscape. Be mindful that if you want your individual house leeks to remain regular , rosette-shape, you’ll need to occasionally thin them out, separating the chicks from their hens. This will prevent them looking “squashed” or from growing upwards, vertically.

Sempervivum can also be propagated by seed germination, but most species will almost never root from taking a leaf cutting (unlike most other succulents).

How to propagate Sempervivum spp.

• Look out for tiny nubs (the start of chicks) that may be forming.
• You will see these as they emerge from near the base of the main rosette, inside the leaves, growing outwards on horizontal stems. These might look more bud-like at first, before starting to resemble the rosette shape of the mother plant.
• You will notice that the stems the chicks are growing on look healthy and in some cases have little leaves along them. This indicates that the chick is still feeding off it’s parent and needs to be left alone to grow, for now.
• You’ll want to wait until they are grown enough to detach – when the chick puts out its own roots and the stolon (horizontal stem) begins to wither and shrivel.
• N.b. If you accidentally knock or break off an offset prematurely, pot it up anyway – it will most likely still grow (waiting will just give it the best chance).
• Once you have identified a chick to propagate, cut or pinch it off. You can use a sharp, clean knife to detach it, carefully cutting through the stem that attaches it to the hen, or simply wiggle it loose.
• Remove any soil or debris that has collected on the separated chick by brushing it off gently.
• Plant the chick –
• Planting in a pot - Fill a pot with an appropriate potting mix and lightly tamp down. Make a shallow hole to plant it into, spread the roots and lightly backfill with soil to give the plantlet some support – don’t plant it too deep.
• Planting in open soil - Make a shallow hole to plant it into, spread the roots and lightly backfill with soil - don’t plant it too deep.
• Planting in a crevice - Poke the roots of the chick into the rock crevice or gap in a wall - backfill with a little soil to secure it.
• Top dress with horticultural grit or gravel – putting it right up underneath the base of the rosette, to stop it getting too wet and to look attractive.
• Don’t water the baby chick for about a week to prevent root rot. Then (if planted in a container and if it has not rained) water sparingly from then on.

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What pests and diseases are Sempervivum likely to get?

They are mostly affected by vine weevil (especially when grown in containers) and Sempervivum leaf miner.

Houseleeks are at risk of developing a fungal disease called Endophyllum rust, as well as being susceptible to crown and root rot. These are all caused by overwatering and can be prevented by growing your plants in free-draining soil and by allowing your plants to dry out between watering. Top-dressing your soil with grit will help to prevent your plant resting on wet soil, and will reduce crown rot.

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Help! I still have a question about my Sempervivum. Can you help me?

If you still have a question about your Sempervivum, please get in touch and I will try to answer you.