Plants in my garden near London (No shelter)

                 Ag. salmiana                                                        Ag. salmiana ssp. crassispina     

     
       Ag. parrasana                                                                      Ag. americana     

     
Ag. filifera                                                                                  Ag. lechuguilla

    
Ag. neomexicana                                                                         Ag. lophantha.

 

 

Agave americana in Cornwall

( photo from Lee Mullin )

     
Agave americana and v. variegata near Bristol
( photos from Nigel Kembrey )

Agaves at Sennen, Cornwall
( photo by Linda Herbert )

 

Kew Gardens, London

Royal Botanical Gardens, Edinburgh

Les Cedres (private succulent collection on Cap Ferrat, Cote D'Azur, France )

Jardin Botanique Nice, Cote d'Azur , France (French National Collection of Agaves)

Jardin Exotique, Monaco

Giardino Esotico Pallanca, Bordighera, Italy

Hanbury Gardens, La Mortola (near Ventimiglia), Italy

Botanical Gardens ( Berggarten ), Hannover

Botanical Gardens, Munich

Palmengarten, Frankfurt

Stadt Sukkulentensammlung, Zurich

'Pinya de Rosa',near Blanes, Spain

'Marimutra' , Blanes, Spain

 

 

This is a topic which can no doubt inspire much fierce debate and controversy and over the years many authors, both professional botanists and agavologists and dedicated amateurs have produced their own lists of plants likely to survive outdoors in a European enviroment. These lists are based on books and literature studied and the individuals own experience. There will always be surprises and plants which appear regularly on hardy lists suddenly rot and die whilst sometimes the most unlikely plants do well. My own experience of this involves a moderately large agave xylonacantha, planted out and completely uncovered, which has now survived unmarked and undamaged during two wet English winters. These hardier agaves are of interest not only to the agave enthusiast but also to the ever increasing band of gardeners, amateur and professional, devoted to creating tropical style gardens in the UK and elsewhere in Europe. Obviously things get easier the further south you go but even in the southern part of France and getting into Italy some agaves may run into problems.

 

The problem for agaves is not so much the cold of the European winter but the wetness and relative humidity. The winter priority is therefore to keep them as dry as possible. This may be achieved by methods ranging from a purpose built structure with a removable roof made from eg. corrugated plastic to simply covering the plants with plastic or other forms of sheeting. There are many excellent and detailed articles in books, journals and on websites describing the principles of building and maintaining a successful outdoor succulent garden and here is not the place to go into further great detail. Suffice it to say that the plants are best grown on a raised bed in well draining soil on a layer of drainage material such as gravel or in my case general rubble left over from building work.

The list produced below is hopefully a useful guide to agaves which have a good chance of doing well outdoors.

 

americana
americana v. mediopicta f. alba**
americana v. marginata/ variegata ( yellow stripe )**
gracilipes
havardiana
lechuguilla
lophantha
neomexicana
palmeri
palmeri v. chrysantha
parrasana
parryi
parryi v. couesii
salmiana
scabra
utahensis
utahensis ssp. kaibabensis
utahensis v. eborispina
utahensis v. nevadensis

 

**The various variegated forms of americana, collectively described as v. picta by Gentry, tend to do less well than the standard blue-grey species plant.

From my own personal experience the best survivors appear to be agave parassana and neomexicana.

 

The following seem to be the most sensitive to cold and wet conditions and are the species most likely to be difficult to grow easily outdoors, especially away from the warmer parts of Europe.

attenuata
gypsophila
guiengola
marmorata
pedunculifera

 

This list is not necessarily complete and based on my own researches. I would value any further input from anyone interested in this topic. Photos welcome.