Repotting guide

When & how to repot Bougainvillea spectabilis (Bougainvillea spectabilis)

Also called great bougainvillea, paper flower.

More about bougainvillea spectabilis

About Bougainvillea spectabilis

Bougainvillea spectabilis · also called great bougainvillea, paper flower · tropical

Great bougainvillea is a thorny, evergreen tropical climber from South America whose vivid magenta, papery bracts surround tiny white true flowers. It blooms hardest in full sun with sparse water — drought stress triggers flowering. Frost-tender, it is grown outdoors in warm climates or under glass in cool ones. Thorns and irritant sap make it best kept away from pets.

Mature size: Up to 8-12 m in the ground in the tropics; kept to 1-3 m in a container or under glass

Watch for — Leaves but no bracts: Too little light, overwatering or too much nitrogen — give maximum sun, keep it on the dry side and feed high-potash.

How to tell bougainvillea spectabilis needs repotting

Repotting on a calendar is less reliable than reading the plant. For bougainvillea spectabilis, 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 bougainvillea spectabilis 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 bougainvillea spectabilis

Every 2–3 years; top-dress in the in-between years. Bougainvillea spectabilis's growth habit — vigorous evergreen woody scrambling climber armed with sharp thorns; needs tying in or training to a support — sets the pace. Great bougainvillea is a thorny, evergreen tropical climber from South America whose vivid magenta, papery bracts surround tiny white true flowers. It blooms hardest in full sun with sparse water — drought stress triggers flowering. Frost-tender, it is grown outdoors in warm climates or under glass in cool ones. Thorns and irritant sap make it best kept away from pets.

What size pot to step bougainvillea spectabilis up to

Move up exactly one pot size. A heavy bougainvillea spectabilis 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 bougainvillea spectabilis

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

Consider top-dressing first. If bougainvillea spectabilis 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 free-draining, fertile, slightly acidic potting mix or soil 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 bougainvillea spectabilis in the same spot and light — moving and repotting at once is what makes it drop leaves.

Aftercare

Leave bougainvillea spectabilis 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 bougainvillea spectabilis

Bougainvillea spectabilis wants free-draining, fertile, slightly acidic potting mix or soil. Demands sharp drainage — use a loam-based compost (such as John Innes No. 2) cut with extra grit or perlite, or a free-draining garden soil. It dislikes heavy, wet ground. In pots, a snug container actually encourages flowering, as restricted roots favour bracts over foliage. Always use fresh mix when you repot — reusing old, broken-down soil reintroduces the compaction and poor drainage you are repotting to fix.

Repotting bougainvillea spectabilis — frequently asked questions

How often should you repot bougainvillea spectabilis?

Every 2–3 years; top-dress in the in-between years for bougainvillea spectabilis. Fully repot bougainvillea spectabilis 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 free-draining, fertile, slightly acidic potting mix or soil. It is heavy and hates being moved, and a vastly oversized pot holds water against the roots and rots them.

What size pot does bougainvillea spectabilis need?

When is the best time of year to repot bougainvillea spectabilis?

Should you top-dress or fully repot bougainvillea spectabilis?

For a big, heavy bougainvillea spectabilis, 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 bougainvillea spectabilis after repotting?

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