I was shocked and a bit devastated when I found out that some succulents die after flowering. It’s not something you should blurt out to a novice succulent lover! But do not worry, of the thousands of different succulents there are only a very small number that are ‘monocarpic’.
Monocarpic plants flower, set seed and then die. Other words with the same meaning are hapaxanth and semelparous. However monocarpic is the term that is used to describe the succulent process. Probably because it is easier to say!
Monocarpic plants can be divided into annuals, biennials and perennials. Annuals flower and set seed in one year, biennials two seasons and perennials sometimes take many years to flower.
So the question is: how long does a succulent live before it flowers?? The good new is: Succulents that are monocarpic can still live a long life as they are perennials. Below are the succulents that I am aware are monocarpic.
Agave – Attenuata/Americana (Century Plant)
The above monocarpic Agave’s can take 10 -25 years before the parent plant flowers. When it is ready the plant uses all its energy to produce a thick stem which grows from the centre of the rosette in a relatively short period of time – sometimes less than a week. The stem can grow up to 2.5 metres (8 feet) high. The Americana (Century Plant) has a stem that can grow to 9 metres (30 feet). Once it flowers the parent plant will wither and die, Compared to other succulents the Agave parent plant can take months or even years to die. Agave pups grow along the stem of the flower, these can be harvested and replanted. Any pups that have grown off to the side of the plant will not die, only the rosette that has produced the flower stem.
Some, but not all, Agave are moncarpic.
All succulents in the Sempervivum genus are monocarpic. At first this made me think twice about buying Sempervivum succulents. Each rosette only flowers once and then dies. However, most species produce lots of offsets which makes up for any loss after flowering. It will take 3 to 4 years for the rosette to produce a flower and die, in this time the parent plant would have produced many pups/babies to continue on in your garden.
In Europe they are known as ‘houseleeks’ but in the USA Sempevervivum are known as Hen & Chicks. However, some people call the Echeveria genus Hen & Chicks as well. Thus, it can get very confusing and people think that their Echeveria succulents are monocarpic. It is ‘only’ Sempervivum Hen & Chicks which are monocarpic not Echeveria.
There are some Sempervivum and Echeveria that look very similar, they both have rosettes. If you think your succulent is a Sempervivum and it flowers – from the centre of the rosette- and does not die – suffice to say this is an Echeveria.
The photos of the sempervivum below show small offsets from the sides. These can be mistaken for flowers. They are not flowers but new plants/pups sprouting. When a Sempervivum flowers it is from the centre of its rosette, not to the side.
Some Aeonium will flower within two years while others may take 10-20 years before they flower. They die completely after flowering but before do they will have produced offsets as well as large numbers of seeds. Not all Aeonium die after flowering, but for the one’s that do it is too late for the plant once the flower stalk starts to develop.
I found this Aeonium (below) in a nursery. It looks very pretty, but as it was flowering I figured it wouldn’t have a very long life span in my garden if it was an Aeonium that was monocarpic! Something to be aware of for monocarpic succulents.
The Kalanchoe ‘Flapjack’ is a monocarpic plant, once the Kalanchoe flowers new “baby plants” can be seen at the base of the plant and along the flower stalk. They can easily be propagated from the stalk.
So, if you have any of the monocarpic succulents you should be prepared for its dramatic flowering death at some point!