Surreal Semponiums

Inspiration

How It Started

Since founding Surreal Succulents, Daniel Michael has created some beautiful Aeonium hybrids which are enjoyed globally, such as Aeonium ‘Phoenix Flame’, Aeonium ‘Emerald Flame’, Aeonium ‘Blood’, Aeonium ‘Cornish Rose‘ and Aeonium ‘Pomegranate’.

With years of experience of hybridising, Daniel had often talked to the RHS botanists about the theoretical chances of crossing other members of the Crassulaea family. 

While some of these such as ‘Pheonix Flame’ are tested frost survivors, generally Aeoniums are tender plants which need protection over winter in the UK. So we started looking at how we could create plants with the beautiful architectural structure of Aeoniums with some of the hardiness of other Succulent species.

What are xSemponiums?

A xSemponiums is an inter-generic hybrid consisting of a Sempervivum and Aeonium. This was possible as they are genetically similar with both being members of the Crassulacean family. 

Sempervivums are generally small compact plants which are extremely hardy and can withstand freezing temperature to below -20. 

Aeoniums tend to be much larger and mostly frost tender, with only a few species and hybrids being able to take frost temperatures. 

How was this possible?

Two plants were used to make these amazing inter-generic hybrids, this may sound easy. However, the flowering season of these plants are very far apart, in fact they are completely different. Aeoniums flower in the months of spring where as Sempervivums flower in the summer months. 

The achievement of getting these two different species to flower at the same time with strong healthy pollen defied the laws of mother nature. 

At the nursery we had a late flowering Aeonium ‘Ice Warrior’ which was moved to one of our coolest spots of the nursery to slow down flowering in an attempt to preserve the pollen. Sempervivum ‘Green Ice’ was chosen being a strong Sempervivum cultivar. 

In our breeding we have found that using hybrids gives you a larger genetic pool with many more possible exciting outcomes rather than using species alone, which gives you less diversity.

This was by no means easy to pull off, the chosen plants had to be carefully contained to stop any cross contamination from other pollinators. These were then often moved in location to speed up or slowdown the flowering process. Once flowering of these two varieties was achieved the attempt of cross pollination could begin. 

With the goal being hardiness, it was decided that the mother plant would be a Sempervivum. The theory was that this would allow us try to maximise the hardiness that the Sempervivum could offer and that we could clearly identify that a hybrid seed was achieved by producing the seed in this plant.

The Aeonium ‘Ice Warrior’ had an abundance of good strong healthy pollen, this plant has an extremely long flowering period over several months. Once flowering there would be hundreds of flowers opening, offering a long window of opportunity.

Sempervivum ‘Green Ice’ will produce a short flower spike with up to twenty flowers only lasting for a few weeks. 

The fresh pollen from the Aeonium ‘Ice Warrior’ was removed and carefully transferred to freshly flowering Sempervivum ‘Green Ice’ using a soft paint brush and tweezers. We kept the flowers away and out of reach of pollinators as we didn’t want cross contamination with other plants.

We then left the flower to ripen in a dry sunny spot for 8 weeks, after this period we collected the flower heads and left them to dry out completely in a brown paper bag for a further 2 weeks.

After the 2 weeks we removed the fine dust like seed from the chaff of the flower, then carefully packaged into a cellophane envelope and clearly labelled it, which was then stored in the fridge for a couple of weeks until sowing.

The seed was then good to go, by that time it was late Autumn, we then took the fine seed and evenly distributed it over the surface of a tray of sterilized seed compost, we then covered the seed with a fine sand and carefully soaked the seed tray in a bath of sterilized water. A thin piece of glass was placed over the top of the seed tray trapping in the humidity to aid germination. The tray was placed in a bright spot and left to do its thing.  

We checked the seed weekly hoping to see signs of germination. By week three we could see signs that the seed had germinated but there wasn’t enough evidence at that point to know if the cross had been successful, more time and patience was needed. A further two to three months on, and to our excitement we saw massive variation in the seedlings, at this point we knew we had done it; we were overcome with emotion as we were witnessing the birth of the world’s first xSemponiums. 

Once the seedlings where at a suitable size we potted every single one on, giving each one star treatment, this was important as we didn’t want to miss any potential prospects. Over the course of the growing season we could select potential forms of interest and colour to grow on, this was an incredibly difficult task as we had so many different amazing looking variations.

We ended up choosing six varieties these all had unique distinctions whether it was form, colour or vigour, each one looked completely different to the next. 

Naming

The speed of growth of all the xSemponiums is fantastic, they grow incredibly quickly with immense hybrid vigour, the leaves look fresh and clean all year round, they also seem to have a shorter dormancy stage than their parentage.

Above all, the hardness of these xSemponiums is one of the most important features of these cross genetic hybrids, with hardness tests still ongoing. And a couple of winters under our belt, we have had xSemponium ‘Sienna’ survive temperatures to as low as -4, this is such an encouraging sign and gives us great hope for future breeding.

RHS

The Semponiums have received great interest and we decided to show them for the first time at the RHS Chelsea Flower Show 2020. Unfortunately, this show was cancelled because of the pandemic. So, the decision was made to save them until the shows return in 2021. 

These plants will all feature in our show garden and we have even entered x Semponium ‘Sienna’ into the ‘Plant of the Year’ competition. 

We are so excited to show case these plants at the world’s most prestigious show. The Semponiums give us a new range of colours, textures and forms to feature in our award-winning show gardens. These plants are so special in their own rights from their parentage, but it is also a chance to show how different and beautiful they are. We are planning to show them alongside many Aeoniums and other succulent plants. We are aiming to highlight that these really are a inter-generic hybrid when showcased in our display garden.

Images © Surreal Succulents & Mimi Connolly