Prehistoric Plants for Today’s Gardens

By Judy Stout

There’s never any guarantee that plants in your landscape will survive. Climate, pests, diseases, and poor plant choices all conspire to affect your garden plants’ survival. Prehistoric plants may be the exception. These are plant species that have withstood the earth’s environmental changes over millions of years. If Mother Nature hasn’t killed them yet, there’s a pretty good chance the average gardener won’t either!

Prehistoric Plants You Can Grow

Prehistoric plants with their “primitive” plant structures are a source of unique forms and textures for your landscape. Their special histories make prehistoric plants great conversation pieces as well! Best of all, many are adapted to a large region of the world so there’s a good chance you’ll discover one or two that will grow well in your own backyard. Here’s a list of plant species that have existed unchanged over millions of years.

Maidenhair Tree, Ginkgo

(Ginkgo biloba)

• Height: 50-80’ (15-24m),
• USDA zones: 4-9

There is fossil evidence that the gingko tree has existed for well over 200 million years, which means that it was present when dinosaurs roamed the earth. Ginkgo is native to China but is now grown throughout the world.

Best known for its unique fan-shaped foliage and unusual growth pattern, ginkgo trees are adaptable to a wide range of locations. You will find them in home landscapes, lining city streets, and even growing in the harsh conditions found in the narrow planting strips of parking lots. Ginkgo is one of the most durable tree species around.

Ginkgos are slow growers that can take many years to go from their somewhat sparse youthful form to a their more lush, broad, mature form. Ginkgo trees are technically conifers with female and male trees that support primitive reproductive structures. The female trees produce nuts that can be eaten if properly prepared. In addition to its use as a food source, ginkgo trees have various medicinal uses in many cultures.

Ginkgo leaves turn brilliant yellow in the fall and it’s not unusual for all the leaves to drop in just a day or two with the arrival of frost, surrounding the trunk with a carpet of yellow and making clean-up easy!

Dawn Redwood

(Metasequoia glyptostroboides)

• Height: 70-130′ (21.3-39.6m)
• USDA zones: 5-9

Dawn redwood has been around for over 90 million years and fossil remains have been found throughout North America, China, and Europe. The dawn redwood was believed extinct until a team of researchers found a pocket of trees growing in a remote region of China. Since its rediscovery, this tree has been reestablished throughout the world.

Dawn redwood is a fast-growing, highly adaptable tree that tolerates moist soil conditions. It’s a good choice for soggy areas of a landscape, near water or a rain garden, but it can also be found in urban settings being grown as a street tree. 

Dawn redwood is a deciduous conifer that, like evergreen conifers, produces small, ½-1” (1.3-2.5 cm) cones. The tree has a beautiful pyramidal shape through most of its lifetime, transforming to a more rounded canopy with maturity. In the fall the foliage turns shades of orange to reddish-brown before it drops for the season. Dawn redwood continues growing late into the fall season making it somewhat susceptible to tip damage from occasional early freezes but on the “plus” side, it has no significant disease or pest problems.

Sago Palm, Sago Cycad

(Cycas revoluta)

• Height: 4-8’ (1.2-2.4m)
• USDA zones: 9-11

Based on fossil evidence, Cycad species have existed for at least 230 million years. The sago palm’s exotic form looks a bit like a palm – hence its common name – but they are not related, and this plant is more accurately called a cycad.

Sago palm (or cycad) is native to areas of Southeastern Japan and the Fujian region of China. The slow-growing plants produce a round, shrub-like mound of stiff fronds when young then gradually take on the appearance of a palm tree as the lower leaves age and drop, leaving the trunk exposed. The leaflets are stiff, shiny deep green. They are dioecious, meaning that there are male and female plants with separate reproductive parts. Male plants produce a pollen-producing cone and females produce a similar globe that will produce seeds.

While there are many species of cycads found throughout the world, the Cycas revoluta species is one of the most popular for use as a houseplant or in landscaping. It’s important to note that all parts of the sago palm are toxic to pets and to humans, with the seeds being especially high in the toxin cycasin. This may not be a plant you want to grow indoors as a houseplant, or outdoors in the landscape, if you have pets or children around.

Horsetail, Scouring Rush

(Equisetum hyemale)

• Height: 2-4’ (.6-1.2m)
• USDA zones: 3-10

Horsetails emerged around 325 million years ago. The scouring rush species is native throughout Eurasia and North American and is just one of 15 species that can be found throughout the world. They thrive in moist soil making this a good choice for planting near a pond, lake, or stream or constantly wet areas in the landscape.    

Horsetail produce hollow stems that don’t branch giving them a strong vertical line that provides an interesting, architectural touch to the landscape. The leaves are small scale-like structures at the stem joints and the tip of the stem is a cone structure that produces spores. Horsetails reproduce by spores but also spread by underground rhizomes.

Wollemi Pine

(Wollemia nobilis)

• Height: 80-130’ (24-39m)       
• USDA zones: 7-9

The Wollemi pine is not a true pine, although it is a conifer and evergreen. This Australian native was discovered in 1994 in a rainforest gorge within the Wollemi National Park in the Blue Mountains, but it can be found in fossils dating back to 90 million years ago. Trees produce attractive frond-like foliage from single, unbranched stems off the main trunk. The distinctive bark has a bubbled texture that is interesting and ornamental. The stems eventually produce a cone at the tip and the entire stem branch will later die. There are two types of cones present on a single tree; one that produces pollen and another that will produce seeds.  

Although it may be difficult to find this critically endangered species for sale at most tree nurseries, it’s not impossible. Plants are slowly becoming more available as seed has been released and it is likely that the Wollemi pine will find its way to many garden centers in the appropriate growing regions. Trees may also be ordered from the Wollemi Pine website.

Whisk Fern, Skeletal Fern

(Psilotum nudum)

• Height: 12-18” (30-45cm)
• USDA zones: 8-10

Whisk fern is considered a weed by many so it may be best to treat this plant as a curiosity and keep it contained to a small space or container. Whisk fern is found growing wild in tropical regions throughout the world including South America, Asia, North America, and Australia. It can be found growing in the ground or as an epiphyte. The Psilotum genus was long thought to be a remnant of the first vascular plants from 400 million years ago. It has more recently been classified as a fern but its primitive form makes it a good fit for a prehistoric garden theme.  

One of the most intriguing features of this plant is that it has no true leaves, flowers, or roots. It absorbs nutrients via root-like hairs and photosynthesis occurs directly through the stems. Reproduction occurs from yellow sporangia balls which produce spores similar to ferns.

Southern Magnolia

(Magnolia grandiflora)

• Height: 50-80’ (15-24m)
• USDA zones: 7-9

Magnolias are one of the oldest flowering species and fossilized magnolias have been found dating back to around 95 million years. One of the more captivating North American native Magnolia species is the southern magnolia. This tree produces bold, glossy, evergreen leaves accented with showy white flowers over a long season from summer into fall.

The blooms last around three days opening in the morning and closing in the evening. This process is a means of trapping beetles in the flower overnight to improve pollination as the insect scrambles around inside (bees were not yet in existence so magnolias evolved with other pollinators). The cone-like seed pods that develop continue this trees’ dramatic features with a display of brilliant red seeds.

Cinnamon Fern

(Osmunda cinnamomea)

• Height: 2-3′ (0.6-0.9m)
• USDA zones: 4-8

Fossils of the cinnamon fern have been found in rocks as old as 70 million years. Ferns in general have been around for over 300 million years so any fern species would be an appropriate addition when creating a prehistoric-themed plant garden. Ferns still retain their primitive reproductive process that involves the release of spores that grow into small plants. It can take years for a fern plant to grow into a mature plant.

Ferns thrive in moist conditions making them an excellent choice for moist, shady garden beds. Their intricate foliage softens the landscape and makes a beautiful filler among flowering plants or for creating interesting textural contrast with broadleaved plants. There are fern species native to regions throughout North America or you can look for cultivars with interesting fronds or colorations.

Moss

Mosses in general have been around for a long time but the Himalayan Takakia moss (Takakia lepidozioides) takes the crown with an age of around 390 million years. If you’re creating a prehistoric themed garden you’ll want to be sure to include moss to add to the authenticity. There are many genera of mosses but if you can find some starts from a moss native to your local area, you’ll have the best chance of establishing it in your landscape. In general moss prefer shady, moist conditions with a substrate such as stone, a log, or a tree trunk. Moss is a natural companion to ferns since they enjoy similar growing conditions.  

Conifers

Conifers are trees that produce their seeds in cones. Any type of conifer tree is a living representation of prehistoric times. Conifers first appeared as far back as 350 million years ago and were a predominant type of tree until more sophisticated flowering trees came on the scene. Conifers are adapted throughout the world and are important both ecologically and commercially. Most are evergreen so they provide year-round color, interest, and refuge for wildlife. Common conifer trees for home landscaping are pine, juniper, cypress, yews, fir, and hemlock trees – just to name a few. Check with a local nursery for conifers suitable for your growing region.

How Did Some Plant Species Survive for Millions of Years?

It’s fair to assume that any plant species that has survived for millions of years must have some advantage over other similar species that went extinct. A list of plant characteristics that could allow plants a survival advantage would include any of the following characteristics:

• Ability to adapt to poor, low-nutrient soils.
• Resistance to diseases and pests.
• Tolerance to a wide range of environmental stresses including heat, fire, and air quality.
• Highly successful reproduction process.
• Spines, thorns, or hairy surfaces that repel animals or insect predators.
• Toxic chemical substances within the plant that deter insect pests.
• Ability to go dormant during unfavorable conditions.
• Rapid growth rate either vertically or horizontally allowing plant to overwhelm competition for light or resources.

Plant enthusiasts might be interested to know that one of the oldest plant species is algae which has existed for at least a billion years according to most scientific timelines. It’s unlikely that most people would consider algae a landscape-worthy plant, but as a prehistoric plant it merits considerable respect!  

Prehistoric Insects for a Prehistoric Garden

The perfect wildlife to go with a prehistoric garden theme is an insect that has been around for over 300 million years – long before the dinosaurs roamed the earth! Dragonflies are not only a pleasure to watch flit about a garden or pond, but these ancient species consume mosquitoes as a key part of their diet. Learn more about how to entice these beneficial insects to your garden in our article Plants to Attract Dragonflies for Natural Mosquito Control.