The Glasshouse Forum considered ways of displaying collections of plants from arid places within a controlled environment, and some of the difficulties of trying to grow, in Scotland, plants that need hot, dry and sunny conditions. Talks were interspersed with tours of the display houses and back-up houses. Pictures brought to the meeting by delegates gave an idea of both the diversity and similarities of our glasshouse displays. The accounts of projects undertaken by RBGE staff in arid regions set a clear context for their glasshouse displays.
Louise Galloway outlined the original concept for the Arid House and some of the future plans for it. There had been visits to the Mojave, Sonoran and Chihuahuan Deserts in the USA and Mexico in 1997 and to Arabia and Africa in 2009. In the Arid House, rocks of different colours were used to denote different parts of the world. The original planting is ‘naturalistic’, showing not only plants from these areas, but also how they are used by animals and people, mechanisms for survival and examples of convergent evolution. These aspects are illustrated for visitors in A Desert Notebook, (by Ian Edwards & David Mitchell) and by sculptures of animals amongst the plants. Annuals (sown in pots and planted out in plugs) that would appear briefly in deserts after rain provided some colour for a few weeks, but some proved difficult to weed in the stone mulch and were prone to whitefly. Susie Kelpie showed us some of the activities they used with visiting children, e.g. folding paper to show how a cactus fills up with water and how overwatering can cause its structure to breakdown, and a display of myrrh and frankincense and their uses.
In a talk about fieldwork in northern Chile in 2008, Clare Morter told us about a journey from Santaigo to Antofagasta, through coastal fogs, Puna vegetation and the cool Atacama Desert, where 50% of the species are endemics. She showed us many, unfamiliar and beautiful plants, e.g. Cistanthe grandiflora, Cristaria viridi-luteola and Copiapoa taltalensis and a clump of Azorella compacta said to be 3000 years old!
Leigh Morris told us about the development of Oman Botanic Garden, in Muscat. It aims to grow only native species, displayed as in the habitats of northern and southern Oman, and to be as sustainable as possible. He showed us pictures of some of the habitats and spectacular scenery – gravel and sandy deserts, seasonal fog forests, wadis, khareef and mountains. RBGE is renowned for research and knowledge of the flora of Arabia, and is helping to set up the new Garden and giving and receiving training for staff of both gardens. It will be the largest botanic garden in the Arabian Peninsula, and a destination for local and international visitors as a ‘centre of learning, recreation, fascination and fun’.
These presentations showed us the range and diversity of the spectacular habitats from which we grow plants in our glasshouses, and the challenge of conveying this to the public. The speakers showed us some of the extraordinary and beautiful plants they encountered. All the talks highlighted the value of horticultural glasshouse staff seeing the plants for themselves in the wild and learning to cultivate and propagate them.
Fiona Inches gave a brief outline of climate control and temperature fluctuations in the glasshouses. David Knott gave us a sneak preview of the new and impressive John Hope Gateway. Our thanks to the staff at RBGE for a stimulating and interesting day.