Repotting guide

When & how to repot Crossvine (Bignonia capreolata)

Also called Crossvine, Trumpet Flower, Quarantine Vine.

More about crossvine

About Crossvine

Bignonia capreolata · also called Crossvine, Trumpet Flower · flowering

Crossvine is a native North American woody vine with tendril-like clinging holdfasts, producing striking reddish-orange and yellow tubular flowers beloved by hummingbirds in spring. Semi-evergreen and adaptable, it tolerates a wide range of soils and is hardy across much of the South and Midwest. Excellent on fences, walls, and pergolas.

Mature size: 9–15 m (30–50 ft) long; can be pruned and kept much smaller. Stems can reach 5 cm in diameter on mature specimens.

Watch for — Invasive spread: Crossvine spreads by root suckers and can become difficult to contain in fertile soils. Install root barriers, remove suckers promptly, and prune annually to maintain boundaries. Not considered invasive in its native range but can be vigorous in enriched garden beds.

How to tell crossvine needs repotting

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

Thick roots out of the drainage holes, or circling the surface and lifting the plant.
The pot dries out unusually fast and crossvine wilts between waterings it used to shrug off.
The plant is visibly top-heavy and tips over easily.
Stalled growth and small new leaves over a full season — though with a big specimen, top-dressing is often the better first response before a full 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 crossvine

Every 2–3 years; top-dress in the in-between years. Crossvine's growth habit — vigorous semi-evergreen woody vine that climbs via branched tendrils with adhesive discs; stems develop a cross-shaped pith pattern visible in cross-section (hence the common name). — sets the pace. Crossvine is a native North American woody vine with tendril-like clinging holdfasts, producing striking reddish-orange and yellow tubular flowers beloved by hummingbirds in spring. Semi-evergreen and adaptable, it tolerates a wide range of soils and is hardy across much of the South and Midwest. Excellent on fences, walls, and pergolas.

What size pot to step crossvine up to

Move up exactly one pot size. A heavy crossvine dropped into a vastly bigger pot sits in a reservoir of wet soil its roots cannot reach, which rots them and destabilises the plant. In the years between repots, lift off and replace the top 3–5 cm of soil (top-dressing) instead — it refreshes nutrients without the shock of a full repot.

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 crossvine

Early spring, just as new growth restarts, is the ideal window for crossvine. 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 crossvine

Consider top-dressing first. If crossvine is not badly root-bound, scrape off and replace the top 3–5 cm of soil instead — far less shock for a big plant that hates moving.
Get help and one size up. For a full repot, choose a pot just one size larger. A heavy plant needs two people and a stable, free-draining pot.
Ease it out on its side. Lay the plant down, slide the pot off, and gently loosen the outer roots. Do not bare-root a mature specimen.
Repot at the same depth. Add fresh adaptable — accepts clay, loam, or sandy soils beneath and around the rootball, keeping the original soil line. Firm it so the trunk is stable and upright.
Water and leave it put. Water thoroughly, then leave crossvine in the same spot and light — moving and repotting at once is what makes it drop leaves.

Aftercare

Leave crossvine in exactly the same spot and light it was in before — moving and repotting at the same time is what makes a big specimen drop leaves. Water it in well, then let the top of the soil dry before watering again so the larger volume of fresh soil does not stay sodden. Do not fertilise for about 4 weeks — fresh mix already carries nutrients and feeding freshly disturbed roots scorches them.

The right soil mix for crossvine

Crossvine wants adaptable — accepts clay, loam, or sandy soils. One of the most soil-tolerant native vines available. Grows well in average garden soil without amendment. Slightly acidic to neutral pH (5.5–7.0) is ideal, but it tolerates a broader range. Good drainage is preferred but not critical. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting crossvine — frequently asked questions

How often should you repot crossvine?

Every 2–3 years; top-dress in the in-between years for crossvine. Fully repot crossvine only every 2–3 years; in the in-between years just top-dress the top 3–5 cm of soil. Step up one pot size in spring with adaptable — accepts clay, loam, or sandy soils. It is heavy and hates being moved, and a vastly oversized pot holds water against the roots and rots them.

What size pot does crossvine need?

When is the best time of year to repot crossvine?

Should you top-dress or fully repot crossvine?

For a big, heavy crossvine, top-dressing — replacing the top 3–5 cm of soil — is the gentler option most years, with a full repot only every 2–3 years. A mature specimen sulks and drops leaves when fully repotted, so do it as rarely as the roots allow.

Should you fertilise crossvine after repotting?

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