Sempervivums or “Hens and Chicks”
“Hens and chicks” are an old favorite of gardeners. Hardy and easy to grow these plants got their common name because the original plant or “hen” produces lots of little plantlets on long stems, dubbed “chicks.” These succulent plants are more properly called Sempervivum tectorum. They are native to Europe and in English gardens are often called houseleeks. In Europe Sempervivums often grew on thatched or slate roofs. The Latin name means “live forever on roofs”.
Sempervivums are rich in garden folklore. It is said when they grow on roofs that they protect the house from lightning and fire. This may have some basis in fact because something green and moist would make it harder for a fire to start, at least on a thatched roof. Grandmothers are supposed to give their grandchildren “chicks” to grow for good luck. Sempervivums are said to be a favorite of fairy gardeners.
Color, form and varieties
Sempervivums or “hens and chicks” come in hundreds of varieties. Most form a loose rosette of fleshy, rounded leaves that grows about 4 inches high. There are some odd shaped varieties with very tight small leaves, some with larger, more pointed leaves and even varieties with rolled or tubular looking leaves. There are very tiny plants and some quite large sized sempervivums.
Sempervivum foliage color is also variable from green to reds, oranges, silver and blues. “Chicks” may vary in color from the “hen” plant and the amount of sun the plant gets will also affect color. Most plants have more than one color in the foliage and color tends to darken in the center or on the tips of leaves.
Some varieties on the market are ‘Booths Red’ a large sempervivum with a bright red starburst look, ‘Pacific Mayfair’ a mixture of tawny orange and red, ‘Aglow’ a brighter orange red, ‘Highland Mist’ a small very dense leaved rosette of green outer leaves and a red center, ‘Big Blue’ a large open rosette of blue gray, ‘Bronco’ a purple black rosette, ‘Lilac Time’ a soft lilac colored rosette, ‘Green Gables’ a tiny green grape colored variety and ‘Oddity’ which has tube like green leaves with red tips.
There are hundreds of other named varieties but those named varieties may be hard to find in your local garden center even though a variety of colors may be offered. If you want named varieties you may need to order from specialty catalogs or on line. Sempervivums can become addictive to plant collectors.
A closely related succulent species, Jovibarba, is sometimes sold as “hens and chicks” also. These require the same care as sempervivums but they don’t produce long stems with the little “chicks” on them, instead the ‘chicks” form near the edges of the mother “hen” plant and are cut out or broken off to form new plants.
Sempervivums are cold hardy, thriving in zones 4-8 and they actually require a period of cold dormancy to grow well. Sempervivums prefer full sun although some will grow in a partly sunny location. Hens and chicks are also drought tolerant and require very little soil to grow. They can grow in rock garden crevices, pots, garden beds, or on topiaries.
Sempervivums require very well drained soil, preferably a sandy loam. If you have heavy clay soil you may want to grow your sempervivums in raised beds or containers that have a light, sandy potting mix in them. You can blend sand, vermiculite or fine gravel with heavier soil in containers or raised beds if needed. They prefer a soil pH that is close to neutral, in the range of 6.5-7.5 but can tolerate slightly more acidic or alkaline soil. Sempervivums or hens and chicks are also grown in sphagnum moss on topiaries.
Sempervivums need to dry out between watering for the best growth. You may want to separate them from garden plants that require more frequent watering. Topiaries are watered by soaking the peat moss or other medium in the topiary frame from time to time. Some sempervivum collectors cover their prized plants with glass or plastic shields when there is a long rainy period so the plants don’t get too wet and rot.
Generally sempervivums don’t require fertilization but when grown on topiary or in a soil-less mix you may want to add a liquid fertilizer to your water a few times in the summer months. Sempervivums have few diseases or pests, with over watering being the most likely cause of problems. Deer and other animals rarely bother them. They do have short root systems and are easily dislodged from their growing area, especially if it is a pot or stone crevice. If you find a dislodged plant quickly replant it and give it just a touch of water.
“Hens and chicks” are short lived perennials. In the third year of life the sempervivum generally produces a flower stalk, which will have tiny star-like pinkish flowers on top. The flowers will produce a dust-like seed that blows away in the wind. After the plant goes to seed it will die. Cutting off the flower stalk will not prevent the plant from dying in the third season. However, it should have left plenty of plantlets behind.
Because they do need a cold dormancy period, most “hens and chicks” do not do well indoors. There are some closely related succulents, Echevera, various crassulas and Aeonium that do better in homes and have a similar appearance.
Propagating “hens and chicks”
As sempervivums grow in a natural setting they produce mats of rosettes from the stolons or stems that grow out from the “hen” with a plantlet or “chick” on the end, which eventually roots near the mother plant. In the garden setting you should try to space your plants so that each plant has a chance to develop a wide rosette shape - about 6-8 inches apart. This helps the plants dry out and prevents rotting at the base. It also makes for a prettier patch.
Sempervivums that are thriving will produce numerous plantlets, sometimes in the first season, almost always in the second and third year. You can take a “chick” off the mother plant at any time to root, but you will be more successful if you wait until the stolen or stem has dried out and the little plantlet has formed a nice rosette. This is generally in late summer. Place the plantlet in slightly moist, well-drained soil and keep watch that it doesn’t get dislodged until it has a chance to anchor itself with new roots. Remember not to give away all of the little plants because the mother plant will die in about 3 years.
Sempervivums do produce seed but it is hard to collect and hard to germinate. Seed grown plants may not look like the parent plants. Plants started from plantlets will sometimes be different from the adult plant also.
Sempervivums or “hens and chicks” are great plants because they thrive with minimal care and provide you with plenty of plants to share and trade. They are an old fashioned plant that is seeing new interest among plant lovers and they well deserve the attention. If you don’t have any in your garden it’s time to get some.