Repotting guide

When & how to repot Crested Floating Heart (Nymphoides cristata)

Also called Crested Floating Heart, Variegated Water Snowflake, White Water Snowflake.

More about crested floating heart

About Crested Floating Heart

Nymphoides cristata · also called Crested Floating Heart, Variegated Water Snowflake · flowering

Crested Floating Heart is a tropical aquatic perennial from Southeast Asia bearing small, heart-shaped floating leaves (3–8 cm) with red-tinged margins and profuse, fragrant white star-shaped flowers with distinctively fringed petals from late spring through early autumn. Fast-growing and suited to tubs and small ponds. Classified as invasive in Florida and several US states — confirm legality before purchase.

Mature size: Floating leaves 3–8 cm across; spread 60–120 cm across open water in a single season; flowers 2–3 cm across held just above the water surface

How to tell crested floating heart needs repotting

Repotting on a calendar is less reliable than reading the plant. For crested floating heart, 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 crested floating heart) 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 crested floating heart

Only every 2–4 years, when genuinely crowded. Crested Floating Heart 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. Rhizomatous floating-leaf aquatic perennial; long petioles rise from submerged rhizomes to carry rounded floating leaves at the water surface; spreads aggressively by stolons and viviparous plantlets that form at leaf bases.

What size pot to step crested floating heart up to

Go up only one pot size — roughly 2–3 cm (about an inch) wider in diameter, no more. Crested Floating Heart 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 crested floating heart 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 crested floating heart

Early spring, just as new growth restarts, is the ideal window for crested floating heart. 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 crested floating heart

Confirm it actually needs it. Slide crested floating heart 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 crested floating heart 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 rich loam or aquatic compost in submerged basket, 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 crested floating heart 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 crested floating heart

Crested Floating Heart wants rich loam or aquatic compost in submerged basket. Plant into heavy loam or aquatic basket compost in a submerged planting basket. A top dressing of pea gravel prevents soil dispersal. Soil should be fertile but avoid overly sandy mixes. In tub gardens, place the basket on a submerged shelf or raise on bricks to achieve the correct water depth. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting crested floating heart — frequently asked questions

How often should you repot crested floating heart?

Only every 2–4 years, when genuinely crowded for crested floating heart. Only repot crested floating heart 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 rich loam or aquatic compost in submerged basket. The key mistake is over-potting: a too-big pot stays wet and rots the roots.

What size pot does crested floating heart need?

When is the best time of year to repot crested floating heart?

Does crested floating heart like to be root-bound?

Yes — crested floating heart 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 crested floating heart after repotting?

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