A blast from the past: three prehistoric plants for the garden

A blast from the past: three prehistoric plants for the garden

The world of plants contains some truly admirable characters that have survived for millions of years, doggedly riding out mass extinctions and outliving the dinosaurs. This group of prehistoric survivors includes some quite unexpected specimens that are still cultivated today in our gardens and across the planet. Did you know that the first magnolias can be traced back 142 to 65 million years? And that fossils of the ancestors of black pepper have been found from between 145 to 100 million years ago?

Including ancient plants in your garden helps to create a lush, jungly feel that’s cooling in summer whilst also looking good on a rainy day. We’re going to delve into three you can grow.

Gingko

Fossils of Gingko biloba or the maidenhair tree have been found dating back 270 million years and fittingly, this delightful garden tree is often referred to as a living fossil. Hailing from China and the only surviving species of an ancient family of trees, it’s rare in the wild and appears on the Red List of endangered species. The leaves, when processed, contain anti-oxidants and are said to have health benefits, including anti-inflammatory properties. It’s also thought that they may help with diseases such as dementia and Alzheimers.

It’s defined as a conifer, although the female cones bear a curious resemblance to olives rather than pine cones. We usually think of conifers as having needle-like leaves but the gingko has unusual, bright green fan-shaped foliage which turns buttery yellow and then falls in autumn.

A robust plant, it does best in well-drained soil in full sun but is fairly tolerant of most soil types. Hardy to -15 degrees C, it can also be incredibly long-lived – the oldest living gingko is thought to be an astonishing 3,500 years old. The main, species form can grow to about 30m tall and 8m in width so is quite large when mature. However there is now a smaller, columnar form, Gingko biloba ‘Fastigiata Blagon’ which only reaches 12 x 4m and is an excellent specimen tree for smaller gardens.

You’ll find more intriguing facts about this venerable tree here:

https://www.kew.org/read-and-watch/ginkgo-biloba-maidenhair-tree-kew-gardens

Tree ferns

There are several tree ferns but the hardiest and most often sold in the UK is the soft tree fern, Dicksonia antarctica. 300-360 million years ago – that’s before the dinosaurs – tree ferns dominated the areas in which they grew. Dicksonias’ native habitat is now South Eastern Australia and Tasmania, where they’re to be found thriving beneath the canopy of larger trees, often eucalyptus, in temperate rainforests. They’re remarkably resilient plants and tend to be amongst the first to begin showing signs of growth after forest fires.

A joy to watch as the spirals of their new foliage unfurl in spring, they can be grown in both borders and containers. Like all plants, they grow best in conditions that mimic their natural environment, in part or dappled shade and ideally, sheltered from winds. They prefer acid to neutral soils and a relatively high degree of humidity so watering is best done by spraying the top and sides of the trunk. (In the wild, water runs down the leaves and over this spongy trunk, which is actually formed from old leaf mass and root material created as the old fronds have died off.)

Dicksonias are slow-growing but eventually reach about 4m in height in the right conditions.  Leaf fronds may remain in place in mild winters but fall in colder temperatures. Although hardy to -5 degrees C, it’s best to protect the crown –from which new foliage emerges – in winter. The safest way to do this is to gently place straw or a ball of hessian into the crown (the top of the trunk) for insulation, and wrap the leaves over the top. Then further wrap the whole thing in horticultural fleece, hessian or old blankets. Needing a bit of care and attention, they’re nevertheless beautiful and rewarding plants.

Cycads

With their fibrous yet handsome trunks and palm-like, sometimes spiky, leaves sprouting from the top, cycads are impressive plants with their origins approximately 280 million years ago. As you might expect from such survivors they usually grow very slowly. A splendid collection can be seen in the glasshouses at Kew Gardens, including ‘the oldest pot plant in the world’ – an Eastern Cape cycad, which arrived at Kew in 1775.

One of the most commonly found in the UK is Cycas revoluta, also known as the sago palm. Not previously thought to be suitable for growing outdoors, they do, however, survive at Ventnor Botanic Gardens on the Isle of Wight and even produced a couple of cones a few years ago, the only time this has happened outdoors in our climate. So they should be hardy enough for warmer or milder areas of the UK.

Usually growing to between 1 and 2m tall, they’ve also been known to reach 3m although this is unlikely outdoors. These evergreen plants like full sun and well-drained soil or compost. Be wary of overwatering as the roots may rot. It’s most convenient and safest to grow a sago palm in a pot so you can move it to a sheltered spot or under cover as winter approaches. Temperatures of less than -5 degrees C will damage the leaves so protect the plant in winter by tying them upwards and wrapping the plant in several layers of horticultural fleece or a couple of old blankets.

You can read about the exciting Ventnor cone event here: www.prolandscapermagazine.com/cycad-produces-male-and-female-cone-at-ventor-botanic-garden/

As you’ll know if you saw Chris Packham’s recent fascinating series ‘Earth’, without prehistoric plants we wouldn’t be here today. Primitive moss, for example, was key to our evolution. Appearing about 450 million years ago, it took carbon from the air, cooling the planet, and created topsoil as it died off and decayed. This allowed the emergence of other plants, which further cooled the atmosphere and increased oxygen levels, setting off a series of events which gave us the breathable air we have today. Moss still has remarkable qualities that help rather than hinder the gardener, coming through extreme conditions which can be the death knell for other plants, soaking up excess water and helping to moderate soil temperature.

Having prehistoric plants in your garden not only adds interest and charm but pays homage to their extraordinary resilience and role in our evolution, as well as acting as a reminder of the plant kingdom’s importance in maintaining a world that we can comfortably live in.