A brief visit to Tromso Arctic-Alpine Botanic Garden

Where is it and what’s special about it?

Tromso Arctic-Alpine Botanic Garden is the most northerly botanic garden on earth (coordinates: 69.68N 18.98E). It is within the grounds of the Tromso University Museum, has no gates, and may be entered freely at any time. It opened in 1994 so is ‘young’ by comparison with most botanic gardens. The garden is nearly all given over to large-scale rock work.

The location within the Arctic Circle, corresponding to the north coast of Alaska, suggests an extreme Arctic climate. However, a branch of the Gulf Stream sweeping up the coast of North Norway provides a moderating influence. Hence the climate of Tromsø is one of relatively mild winters (January average −4.4 °C) and cool summers (July average 11.7 °C). The growing season in the Botanic Garden is usually from the end of May until mid October. From May 15 until July 27, the sun is continuously above the horizon. This period of ‘midnight sun’ provide some compensation to the plants for the short growing season and the low temperatures, providing an average of 200 hours of actual sunshine each of the months from May-July. From November 21 until January 17 the sun never rises. Snow cover generally persists from October or November until the beginning of April.

The plant collections at the Tromso Alpine Botanic Garden

The impressive (mostly igneous) rock work, set on a steep-ish, sunny bank, acts as a suitable backdrop for displays of plants from arctic regions and from many major mountain ranges of the world. Particularly notable are perhaps the finest outdoor collections anywhere of cold-tolerant Himalayan and South American species. There are also major acquisitions from the vast Caucasus region, Australasia, North America and the European Alps.

These geographical collections are mostly grouped in designated areas. But there are also beds representing individual plant families or genera. These include a collection of saxifrages that is probably the best outdoor assemblage anywhere. Rhododendron and other Ericaceae,  Primulaceae (especially primulas), Meconopsis (an especially fine and comprehensive collection), Ranunculaceae (including a splendid selection of Anemone and its close relatives, and luscious eye-catching plantings of Trollius). Iris (especially Himalayan and Caucasian species), Codonopsis, Aster, Erigeron, Polemonium are also well represented.

I was surprised, but delighted, to find an unexpectedly varied and excellent collection of Fritillaria, many of which would not even be considered for outdoor cultivation in the UK. Unfortunately most were past their best at the time of our visit, June 11, and not suitable for photography.

What did we see?

Our visit seemed to fall in an ‘in-between’ period. The early bulbs and snow-melt arctic-alpines, plus most South American plants, were past their best. At the same time, the Himalayan species were mostly only just coming to their peak. Also, time constraints (we were on an Arctic cruise!) meant that we only had an hour or so to spend, so it is a fairly cursory ‘look-see’ that I present to you here.

Meconopsis at Tromso Alpine Botanic Garden

Pride of place must go to the genus which provides so many outstanding species for those of us who garden in conditions to which they are suited, which may be summed up as ‘not too dry and not too hot’. The climate at Tromsø clearly favours them. Here are a few that were at or near their best.

M. quintuplinervia

Farrer’s ‘Harebell poppy’ seen here growing through a carpet of the delightful little Viola biflora. This is a short-lived perennial species that increases by runners.

M. integrifolia

Another with a Farrer nickname, in this case ‘Lampshade poppy’. One of the many monocarpic species that die after flowering, which usually occurs in their second year from seed.

M. sulphurea

Rare in cultivation, probably chiefly because seed is difficult to come by and as with all other monocarpic species this is the only means of increase.

M. grandis

Regarded by many as the finest Himalayan blue poppy. When grown well in ideal conditions, i.e. acidic humus-rich soil, adequate moisture, shelter from wind exposure, it can be a long-lived perennial.

Primulaceae

There were far too many primulas and their relatives to show all, so here are a few that took my eye while on our visit to Tromso Alpine Botanic Garden.

P. auricula

There were several forms and hybrids of this grand old species that has graced our gardens for hundreds of years. This one appealed to me and I love the way it looks so natural in its rock cleft, just as it does in the Alps.

Primula matthioli (syn. Cortusa matthioli)

This clearly loves the conditions, forming large clumps and seeding around.

Androsace sempervivoides (with Corydalis ? flexuosa)

See how this delectable tiny primula relative runs around in the mossy substrate, gradually forming a large mat. It can do the same in a damp, lightly shaded spot in your garden.

Omphalogramma sp.

Eclipsing all other members of its august family as far as I was concerned was a wonderful example of  the genus Omphalogramma. Labelled (possibly incorrectly?) O. elwesiana, this small clump brought an involuntary ‘ooooh’ to my lips when I spotted it. Purple is probably my favourite colour anyway and this was Tyrian perfection. One rarely sees Omphalogrammas in British gardens, certainly in the south of England. Where they do deign to grow they are rarely long-lived, usually cosseted in a pot. If you have the chance, give them shade and constant humidity, drying out is invariably fatal.

Ranunculaceae at Tromso Alpine Botanic Garden

This great family furnishes a whole host of plants suitable for the alpine garden and its environs. Many are tiny treasures, such as the alpine buttercups (Ranuncuulus spp.) that adorn many a high scree and alpine meadow of mountains throughout the northern and southern hemispheres. There were examples of these but they were past their best, being among the earliest plants to rush into bloom as the snow melts.

More brash, but no less beautiful, are some of the larger members of the family. Among these, anemones and globeflowers (Trollius sp.) held pride of place, glorying in the cool, moist atmosphere.

Anemone narcissiflora

This windflower, common as it is, ranks at the top among the aristocracy of the high alpine pastures. There were large clumps of various forms, including the pink-flowered A. narcissiflora subsp. crinita.  I had not seen this before but should like to try and grow it.

Anemone obtusiloba

This fine anemone hails from the damp mountain meadows of India, Pakistan and into Tibet and W. China. It ranges in colour from various shades of blue-violet to white and  creamy yellow. All these colour forms were growing in the garden. If my experience with blue forms is anything to go by, it is an easy long-lived plant in a moist semi-shaded spot.

Trollius europaeus

I remember many years ago clambering over a rocky rise near the Pordoi Pass in the Dolomites and looking down upon a ‘field’ of gold as wonderful as any buttercup blanketed pasture at home. But it was another member of the buttercup family, ‘globe flower’, that provided such a memorable image on that day. I have seen it many times since, often in the UK where it is locally common in upland areas on moist alkaline soils.

Finally, I cannot leave this brief account of my visit to Tromso Alpine Botanic Garden, without showing you an eye-piercing patch of Tulipa linifolia in all it’s fleeting glory. What a surprise to find it in fine fettle on a hillside inside the Arctic Circle, far from its home in Tajikistan, Uzbekistan, northern Iran and Afghanistan.

About the author

John has travelled and lectured widely on alpines and written many articles and several books on the subject, the latter leading to his having served as AGS Director of Publications and Assistant Editor of our journal. He has also always been heavily involved in his local North Wales Group.

Read John’s garden diary entries here.