Hike along any low-elevation stream in the Cascades and you’re likely to pass colonies of Tolmiea menziesii — more commonly known as the piggyback plant. These humble plants draw their common name from a unique habit of sprouting new plants on top of their leaves (reflected in other common names for the species, including “youth-on-age” and “thousand mothers”).
The botanical name for this species memorializes two giants in the early days of Pacific Northwest botanical discovery: Scottish-Canadian botanist William Fraser Tolmie and Archibald Menzies, the Scottish naturalist for the Vancouver Expedition.
These fuzzy little plants thrive in the moist shade of streamside broadleaf trees like red alder and bigleaf maple. As forest floor dwellers, piggyback plants have become expert at reproducing. They can spread along their well-developed rhizomes, through seeds, and of course, through the tiny plantlets that form on their leaves.
A close look at the piggyback plant reveals a whorl of basal leaves, typical of the many species in the saxifrage family. The leaves have 5-7 lobes, and are finely toothed. Both leaves and stems are covered in fine white hairs that give them a soft texture to the touch.
Piggyback plants produce leaves continually from their base, with larger, older leaves eventually sprouting a “daughter” plantlet. The genius of this reproductive strategy is how it fits into the life cycle of the deciduous forests where the plants thrive. As the older leaves mature, they extend away from the mother plant on 4-6” stems, allowing daughter plantlets that form to touch down well away from the parent plant.
This is where the over-story of deciduous trees come in. Daughter plantlets form mostly over the course of the spring and summer growing season, By autumn, they are ready for falling maple and alder leaves to bury them, pressing tiny rootlets on the daughter plants into contact with the ground, where they can grow and anchor the new plant.
By the next spring, the new plant is ready to grow on its own, still fed by the nutrients from the fading mother leaf, and still with the connecting stem from the mother leaf forming an umbilical cord to the mother plant. Over time, the mother leaf and stem connecting to the daughter plant wither and die, and the daughter becomes truly independent from the parent.
In spring, piggyback plants produce clusters of tiny, graceful blossoms on 6-10” spikes. Each blossom is capable of producing a small seed capsule filled with tiny seeds. Flower stalks die back over the course of a summer, releasing seeds to grow side-by-side with the cloned plants that have sprouted from rhizomes and “piggyback” plantlets.
As a survival strategy, the seed offspring have the advantage of being cross-pollinated. Over time, seed-based offspring can evolve with the genes of two parents to have new survival characteristics that single parent cloned plants from root or leaf starts inherently lack.
Piggyback Plants in the Commercial Trade
Only a few native plants from Pacific Northwest forests have been hybridized to become commercial cultivars, and still fewer are suitable as indoor plants. The piggyback plant fills this rare niche, somehow adapting to the relatively hot, arid conditions indoors. They are typically sold as hanging basket plants.
The curious “piggyback” habit is the main attraction for growing the plants indoors. Breeders have created commercial hybrids with larger leaves, more “piggyback” plantlets and even a few variegated cultivars, such as the “Taffs Gold” Tolmiea shown above.
Starting Your Own Piggyback Plant
There’s no need to buy a piggyback plant, kids (and parents) can enjoy collecting and growing piggyback plants collected in the wild. You can make this a two-part adventure for kids by combining the collecting with a day hike, then propagating what you’ve collected at home.
Piggyback plants are plentiful along several family-friendly trails in the Columbia River Gorge: notable among these are the short trails to Latourell Falls, Bridal Veil Falls, Elowah Falls and Wahclella Falls.
On each trail, you’ll find piggyback plants in streamside areas and where deciduous trees grow. Your kids will quickly learn to spot them, and it’s okay to collect a few plantlets for growing at home, as you will be leaving the mother plant behind to produce more (an important lesson for kids).
To grow your daughter plant, you’ll need the following:
• small pot (3-4 inches)
• soil-less potting mix
• bobby pin (or paper clip)
• rubber band
• plastic sandwich or freezer bag
Planting your starts is simple: (1) fill the pot to within 1” of the top with soil; (2) place the mother leaf and plantlet in the pot, with rootlets touching the soil; pin in place by pushing the bobby pin (or paper clip) over the mother leaf stem just below the plantlet, and holding it against the soil. Next, (3) sprinkle another 1/4” of potting mix, slightly covering the stem and base of the plantlet, and water well. Finally, (4) secure the plastic bag over the pot with the rubber band to provide a humid environment for the young plantlet to become established.
Keep your new piggyback plant in a bright north or east-facing window, and covered with the plastic bag until you see the plantlet growing. At this point, you can remove the bag and watch your new houseplant grow — or plant it in your yard, where it will thrive in moist shade.
This is a terrific way to get young kids excited about the outdoors, and perhaps develop a green thumb in the process! You can start a piggyback plant at any time, as the plantlets can be collected year-round on the low-elevation Gorge trails listed above.