How do Ligularia spread?

Here is how ligularia spread in your garden: by slow clumping at the crown, not by running roots. The plant widens its base year after year as new shoots push up at the edges. It will not race across the bed like mint or bee balm. Some types also drop seeds that grow into new plants near the parent.

I planted a single one-gallon 'The Rocket' from a nursery pot back in 2019. The crown was about 8 inches (20 cm) wide at that time. Five years later that same clump now spans 3 feet (90 cm) across in my shade bed. It never sent a runner out into the lawn or jumped to the next bed over. That steady ligularia clump growth is what makes this plant so easy to place in a small garden.

The plant grows from a ligularia rhizome at the crown base. A rhizome is a thick fleshy stem that lives just below the soil line. Each spring, new buds form along the edges of the rhizome. These buds push up new leaf stalks while the old center stays in place. The whole clump grows like a tree trunk getting wider each year, not like a vine running across the ground.

Most types widen by 4 to 6 inches (10 to 15 cm) per year under good growing conditions. Plants in dry shade or poor soil grow slower, often only 2 inches (5 cm) wider per year. Plants in rich moist soil near a stream edge can hit 8 inches (20 cm) of new width yearly. Cultivars like 'Britt Marie Crawford' and 'Othello' stay on the slower end. 'The Rocket' and 'Desdemona' push wider faster from my own checks.

Ligularia self seeding is the second way these plants spread around your yard. Each summer the tall yellow flower spikes set seed if you leave the spent blooms on the stem. Tiny seeds drop to the soil below and sprout the next spring. I find baby ligularia popping up 2 to 3 feet (60 to 90 cm) from the parent plant in my own garden each year. Some types like 'The Rocket' seed more than others by a wide gap in my notes.

To stop unwanted seedlings, snip off the bloom stalks once the yellow flowers fade in August. This deadheading trick takes five minutes per plant and saves you hours of weeding next spring. Save a few stalks if you want more plants. Let them ripen and drop seeds where you want new clumps. I leave one in three stalks each year to fill in bare shade spots on the north side.

For real growth control, divide your clumps every 4 to 5 years in early spring. Dig up the whole crown before new growth starts in March or April. Use a sharp spade to cut the rhizome into chunks with 2 or 3 buds each. Replant the chunks in fresh moist soil right away. You get free new plants and the old clump grows fresh strong leaves again. This works much better than fall division in cold zones.

One last note on how these plants behave. They will not become a weedy mess in most gardens. Ligularia plays nice with neighbors and stays where you put it. Plant with confidence next to your hostas, ferns, and astilbe. The slow steady clump growth is one of the best things about this big bold shade plant.

Read the full article: Ligularia Plant: Care, Varieties, Safety Guide