Repotting guide

When & how to repot Showy Tick Trefoil (Desmodium canadense)

Also called Showy tick trefoil, Canada tick trefoil, Showy tick clover.

More about showy tick trefoil

About Showy Tick Trefoil

Desmodium canadense · also called Showy tick trefoil, Canada tick trefoil · flowering

Desmodium canadense is a tall, robust native perennial wildflower of moist prairies, thicket edges, and open woodland borders across eastern and central North America, from Nova Scotia to Saskatchewan and south to Oklahoma and North Carolina. It produces showy rose-pink to purple pea-like flowers in branched racemes in mid- to late summer, making it one of the most ornamentally valuable of the native tick trefoils for pollinator gardens. It tolerates a broader range of soil moisture than most prairie natives and self-seeds freely. It is not listed as toxic to cats or dogs by the ASPCA, though its seed pods attach to fur and clothing via hooked hairs.

Mature size: 90–180 cm (3–6 ft) tall and 60–90 cm (24–36 in) wide.

How to tell showy tick trefoil needs repotting

Repotting on a calendar is less reliable than reading the plant. For showy tick trefoil, watch for these signs:

Roots spiralling thickly out of the drainage holes or pushing the whole plant up out of the pot.
The pot is so packed that water runs straight through in seconds and barely wets the soil.
It has split a plastic pot, or the rootball is a solid mass with almost no soil left when you slide it out.
Growth and (for showy tick trefoil) flowering have clearly stalled despite good light and feeding — but remember this plant likes being snug, so a little crowding alone is not a reason to repot.

For the underlying biology of a pot-bound root system and why it stalls a plant, see our guide to spotting and fixing a root-bound plant.

How often to repot showy tick trefoil

Only every 2–4 years, when genuinely crowded. Showy Tick Trefoil is one of the plants that genuinely prefers a snug pot — it grows and flowers better with its roots a little restricted, so resist the urge to repot it on schedule. Upright, branching clump-forming perennial with stout stems bearing trifoliate leaves and open branched racemes of pink-purple flowers in July–September..

What size pot to step showy tick trefoil up to

Go up only one pot size — roughly 2–3 cm (about an inch) wider in diameter, no more. Showy Tick Trefoil positively prefers a snug pot: it flowers and grows better when the roots are a little restricted. The single biggest repotting mistake here is over-potting — dropping showy tick trefoil into a pot two or three sizes up. All that surplus soil holds water the small root system cannot use, stays cold and wet, and rots the roots within weeks. When in doubt, choose the smaller pot.

Not sure of the exact diameter? Our pot size calculator takes the current pot and root spread and tells you the right next size — it deliberately recommends a single step up, never a big jump.

The best time of year to repot showy tick trefoil

Early spring, just as new growth restarts, is the ideal window for showy tick trefoil. The plant is moving into its strongest growth phase and re-roots into fresh soil quickly. Avoid repotting in winter dormancy or, for flowering plants, while it is in bud or bloom — recovery is slowest then and you risk dropping the flowers.

Step-by-step: repotting showy tick trefoil

Confirm it actually needs it. Slide showy tick trefoil out and check the roots. Only continue if it is genuinely packed — this plant prefers a snug pot, so if there is still soil and room, put it straight back.
Pick a pot only one size up. Choose a pot just 2–3 cm wider with good drainage. Resist anything bigger; over-potting is the main killer here.
Ease it out gently. Water lightly the day before, then tip showy tick trefoil out, supporting the base. Tease the outer roots free only enough to stop them circling.
Repot at the same depth. Add a layer of fresh moist loam, clay-loam, or sandy loam; ph 5.5–7.0, set the plant so the soil line sits exactly where it did before, and backfill around the sides, firming lightly.
Settle it in. Water once to settle the soil, then let it sit. Hold off on more water until the top of the soil dries — fresh soil around a small root system stays wet for a while.

Aftercare

Because the new soil holds more water than the old crammed rootball did, ease right back on watering — let the top of the soil dry before you water showy tick trefoil again, or you will rot the roots in the very pot you just moved it to. Keep it out of harsh direct sun for a fortnight. Do not fertilise for about 4 weeks — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for showy tick trefoil

Showy Tick Trefoil wants moist loam, clay-loam, or sandy loam; ph 5.5–7.0. Adaptable to a range of soil textures from sandy to moderately heavy clay; fixes its own nitrogen so lean native soils require no amendment. Mulching retains moisture and moderates soil temperature. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting showy tick trefoil — frequently asked questions

How often should you repot showy tick trefoil?

Only every 2–4 years, when genuinely crowded for showy tick trefoil. Only repot showy tick trefoil every 2–4 years, and only when it is genuinely root-bound — it flowers and grows best slightly crowded. Step up just one pot size in spring using moist loam, clay-loam, or sandy loam; ph 5.5–7.0. The key mistake is over-potting: a too-big pot stays wet and rots the roots.

What size pot does showy tick trefoil need?

When is the best time of year to repot showy tick trefoil?

Does showy tick trefoil like to be root-bound?

Yes — showy tick trefoil genuinely flowers and grows best when slightly pot-bound, so do not rush to repot it. The mistake to avoid is over-potting into a much larger pot: the excess soil stays wet, the roots cannot use it, and the plant rots. Only repot every few years and only one snug size up.

Should you fertilise showy tick trefoil after repotting?

Not immediately. Wait about 4 weeks after repotting showy tick trefoil. Fresh mix already contains nutrients, and feeding freshly cut or disturbed roots burns them. Resume your normal feeding routine once you see new growth.