Repotting guide

When & how to repot Common Bird's-foot Trefoil (Lotus corniculatus)

Also called Common Bird's-foot Trefoil, Bird's-foot Trefoil, Eggs and Bacon.

More about common bird's-foot trefoil

About Common Bird's-foot Trefoil

Lotus corniculatus · also called Common Bird's-foot Trefoil, Bird's-foot Trefoil · flowering

Lotus corniculatus is a low-growing perennial wildflower native to grasslands across Europe, Asia, and North Africa, widely naturalised in North America. It thrives in full sun on poor, well-drained, low-nitrogen soils — excessive fertility encourages leafy growth at the expense of flowers. As a legume it fixes atmospheric nitrogen through root nodal bacteria, so avoid enriching the soil. The plant contains cyanogenic glycosides (primarily lotaustralin) and is considered mildly toxic to pets if ingested in quantity.

Mature size: 10–40 cm tall, spreading to 30–60 cm wide.

Watch for — Fusarium wilt: Fusarium oxysporum can colonise roots in wet or poorly drained soil, causing sudden wilting and browning; improve drainage and avoid overwatering.

How to tell common bird's-foot trefoil needs repotting

Repotting on a calendar is less reliable than reading the plant. For common bird's-foot 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 common bird's-foot 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 common bird's-foot trefoil

Only every 2–4 years, when genuinely crowded. Common Bird's-foot 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. Prostrate to ascending, mat-forming perennial with slender branching stems reaching 10–40 cm..

What size pot to step common bird's-foot trefoil up to

Go up only one pot size — roughly 2–3 cm (about an inch) wider in diameter, no more. Common Bird's-foot 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 common bird's-foot 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 common bird's-foot trefoil

Early spring, just as new growth restarts, is the ideal window for common bird's-foot 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 common bird's-foot trefoil

Confirm it actually needs it. Slide common bird's-foot 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 common bird's-foot 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 well-drained, low-fertility, 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 common bird's-foot 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 common bird's-foot trefoil

Common Bird's-foot Trefoil wants well-drained, low-fertility. Thrives in sandy or chalky soils with a neutral to slightly alkaline pH (6.5–8.0); avoid clay or enriched garden soil as high nitrogen suppresses flowering and nitrogen-fixation. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting common bird's-foot trefoil — frequently asked questions

How often should you repot common bird's-foot trefoil?

Only every 2–4 years, when genuinely crowded for common bird's-foot trefoil. Only repot common bird's-foot 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 well-drained, low-fertility. The key mistake is over-potting: a too-big pot stays wet and rots the roots.

What size pot does common bird's-foot trefoil need?

When is the best time of year to repot common bird's-foot trefoil?

Does common bird's-foot trefoil like to be root-bound?

Yes — common bird's-foot 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 common bird's-foot trefoil after repotting?

Not immediately. Wait about 4 weeks after repotting common bird's-foot 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.