Winter in the alpine department – December 2023

The main Rock garden in late December

I am aware that not everyone will have been to see the Rock Garden at Wisley. I thought a few views of the area may therefore be helpful.

The Larix pool

This speciment of Larix kaempferi was presented to the RHS by James Carter & Co, in June 1905, having been imported from Japan in 1904. At the time it was estimated to be 100 years old. I believe the significance of the age of the tree was that the Horticultural Society of London was founded on 07 March 1804. This Society became the RHS when it was granted a Royal Charter, following the appointment of Prince Albert as President of the Society in 1861.
A tree that was 100 years old to mark the one hundred year anniversary seems very appropriate. It has grown a little over the years.

The Carnivorous bed was re-planted in 2022

The construction of this bed was featured in another of Paul Cumbleton’s Wisley posts. The bed had become infested with Equisetum arvense  (mare’s tail) and Erythranthe guttatus (syn. Mimulus guttatus). In line with the RHS policy of going peat free, it was dug out and replanted in 2021 / 22 with a mix of 2 parts of reconstituted coir, 2 parts reconstituted sphagnum moss, 1 part composted pine bark and 1 part grit.

The Equisetum will come back but hopefully it can be managed to an acceptable level. Many visitors don’t believe that the Sarracenia are frost hardy and need not be re-planted every year. They survived -10°C in January 2023, so they are fairly hardy. The black cable at the bottom left of the picture is part of the Wisley glow festival and not some secret soil heating system.

The Rock garden planting is always changing

This bed was cleared a few weeks ago and will be planted in spring 2024. There was a lot of Lysichiton americanus (American skunk cabbage) that had taken hold. The roots go down about 60cm. Many large holes had to be made to extract the plants. The holes were then filled in with compost. The ropes are another of the Glow temporary light display.

A large Pieris was also removed in the autumn. The retaining wall was planted with Lewisia cotyledon and saxifrage cuttings from the collections in the Rovero greenhouse.

The Wisteria bridges were replaced this year

The old wooden Wisteria bridges linking the alpine meadow to the Oak Wood were replaced in 2023. They were in need of extensive repairs. The old design wasn’t wide enough for mobility scooters and visitors, who often pause on the bridges to admire the views. The rust finish complemented the autumn colours wonderfully a few months ago. The Wisteria is still there and will be re-attached in 2024. New benches were also provided. Whenever I look at them, I’m reminded of the 1992 novel by Robert James Waller, The Bridges of Madison County. Come to Wisley for your own romantic adventure.

The Crevice garden stones have weathered over the years

In spring the colour will return. Paul featured the construction of this area in 2011, to mark the 100 year anniversary of the construction of the main Rock Garden. Even at this time of the year Zdeneck Zvolanek’s design makes a bold statement.

There is plenty of colour in the Alpine Display House

There are many snowdrops and early Narcissus on show alongside other interesting alpines.

We are grateful to Carina Moffat for the lockable display case

If you’ve not been to the Rock garden for a few years, another improvement took place in 2018 with the addition of the lockable display case. This sadly was necessary to help reduce plant thefts. Carina also supplied some of the snowdrops having taken over her father’s collection when his health deteriorated. Her father was Douglas Gardiner (1921 – 2015); he was a very keen Galanthus grower and friend of the RHS and Wisley. You can read his obituary in the Kings College Cambridge annual report 2016.  Sadly Carina was taken from us in 2021, at the age of 70.

I hope that we are doing the memory of Carina and Douglas proud with a fine display of snowdrops currently on show. I always thought that having a surname like Gardener / Gardiner would be of help if you were horticulturally minded. A good example of nominative determinism.

Plants in flower in the Alpine Display House

Colchicum trigynum used to be called Merendera caucasica and can be found growing from Turkey to the Caucasus and north west Iran. The flowers can also be pink and some are tessellated with purple or darker pink. The specific epithet is from the Latin tri – three and gynum – relating to the ovary. I used to think that colchicums were all autumn-flowering, and that they should have long since stopped flowering.

Sternbergia candida was first discovered in 1979. The species is found growing on the edges of cedar forests in the Mugla province of south west Turkey, on semi-shaded rocky ground. The flowers are scented. Another example of a genus that I thought was autumn-flowering only.

Gypsophila aretioides hails from the Caucasus mountains in northern Iran. It sometimes produces a few white flowers but it is mainly grown for its shape. This plant should be nicely domed but is displaying the sign of many small hands (and a few large ones, that should know better) giving it a pat. The RHS doesn’t want to put up signs saying “don’t touch”. If ever you are tempted to judge the quality of some of the plants on display, please remember what they go through.

Petrocosmea grandiflora hails from southeastern Yunnan and grows on limestone cliffs at around 200m. It is classed as a tender alpine. The genus was named in 1887. From the Greek petra – stone / rock and from the Latin cosmos – beautiful. The specific epithet is from the Latin grandi – large / showy / big and flora – the Roman goddess of flowering plants. It certainly makes a very pretty flowering rock. Mainly, the genus consists of lithophytes – species growing on damp rocks. They are members of the Gesneriaceae family that includes African violets. Like African violets they do not like being too damp and can rot like African violets do. This species was introduced into cultivation in the late 1990’s. It was known then as P. duclouxii.