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Buddleia buying guide

Updated: 22 October 2026

You are about to order a butterfly bush from amazon.co.uk, and the photograph shows a shrub in full spike. The line you pay for may be a 9 cm liner, a 2 litre pot, or a pack whose star line belongs to another size. This buddleia buying guide is the checklist before you buy. It does not rank the six listings. Prices and scores sit on the [buddleia comparison](/hub/ornamental-plants/buddleia). Peter F. checked the amazon.co.uk listings and public UK sources on 21 October 2026. These plants were not grown in a trial. A qualifying purchase through our links can earn a commission at no extra cost to you.

You are about to order a butterfly bush from amazon.co.uk, and the photograph shows a shrub in full spike. The line you pay for may be a 9 cm liner, a 2 litre pot, or a pack whose star line belongs to another size.

Our top picks

Carbeth Plants Tricolour buddleia, one 2 L pot

Best overall

Carbeth Plants Tricolour buddleia, one 2 L pot
8.2/10about £19.99
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Carbeth Plants Buddleia trio, three 9 cm pots

Best value

Carbeth Plants Buddleia trio, three 9 cm pots
7.3/10about £17.99
View offer
Carbeth Plants Flower Power buddleia, two 2 L pots

Alternative

Carbeth Plants Flower Power buddleia, two 2 L pots
6.2/10about £24.99
View offer
On this page
  1. 1.What the pot and the piece count are saying
  2. 2.Whose height is on the attribute line
  3. 3.Colour words and shared star lines
  4. 4.Hardiness, seed and the passport

What the pot and the piece count are saying

The RHS growing guide treats 2–3 litre nursery pots as the usual start for buddleja. A smaller pot often needs about an extra year before it looks like the photograph. These listings include one 2 litre tricolour at about £19.99, a title for three 2 litre tricolour pots at about £46.99, Flower Power packs titled as two or three 2 litre pots, and 9 cm trios at about £17.99 and about £14.45. Those figures are root volume, separate from the patio container you may need later. Flower Power lists number of items as 2 or 3 while unit count stays 1.0. White Profusion shows unit count 1.0 with three pieces. The three-pot tricolour title says three 2 litre pots, and one bullet describes three plants grown in a single pot. Count separate rootballs when you unpack. A 9 cm pot is a young plant. The RHS pot of about 60 cm wide is for dwarfs such as Buzz or Nanho, and neither is in this set.

Whose height is on the attribute line

Buddleja davidii on the RHS plant page is deciduous and hardy to H6, about 2.5–4 metres tall and 4–8 metres wide. Hard pruning from late March to mid-April holds the framework at about 1.8–2.4 metres. The single 2 litre tricolour prints 60 cm. The three-pot tricolour repeats 60 cm, and a bullet says 2 metres. White Profusion shows 9 cm, the pot diameter entered as height. Flower Power prints 2 metres. The RHS page for Buddleja × weyeriana 'Bicolor', the Flower Power synonym, gives 2.5–4 metres tall and a spread of 1.5–2.5 metres. A centimetre figure on the marketplace is what the seller typed. The 60 cm line sits beside deciduous davidii copy, and the listing does not name Buzz or Nanho.
Carbeth Plants Tricolour buddleia, one 2 L pot

Testsieger

Carbeth Plants Tricolour buddleia, one 2 L pot
8.2/10about £19.99
View offer

Colour words and shared star lines

Tricolour is a seller phrase for pink, white and purple. Stored reviews on those listings mention colours short of three on one shrub. The 9 cm trio at about £17.99 states dark blue, red and white, and a bullet says the mix may differ from the picture. Reviews on that listing often report one colour, especially purple or blue, and some parcels include a dead or very small plant. Both tricolour listings print 4.0 from 425, and the stored texts match, including comments about one 2 litre plant and an old £18.99 price. The three-pot shelf price is about £46.99. Both Flower Power listings print 3.7 from 10, with the same five stored texts about a single plant. Jobs for each listing are on best buddleia in this set.

Hardiness, seed and the passport

The RHS lists H6 for Buddleja davidii, hardy throughout the UK. Non-native species guidance for England, Scotland and Wales notes that davidii spreads by seed. Schedule 9, as retrieved, does not name Buddleja. This page does not say the plant is illegal in a private garden. Deadhead spent spikes if you want fewer seedlings near walls and paving. GOV.UK requires a UK plant passport on distance sales of plants for planting in Great Britain. None of these listings mentions a passport on the page. That is a paperwork gap for the seller, and a reason to buy from a source you trust when the label already disagrees with itself. The cut is on how to prune buddleia.

Common questions

Is a 9 cm buddleia a finished shrub or a liner?
It is a liner. Expect seasons of growth before it behaves like a border plant. If a cultivar is named, use the RHS mature size for that plant. The pot diameter on the listing is the arrival size.
Does tricolour mean three colours on one plant?
The listing claims pink, white and purple. Reviews on the tricolour packs and the 9 cm trio report fewer colours than the photograph suggests. Treat tricolour as a marketing mix. It is a weak promise of three hues on every spike.
Can I trust 4.0 from 425 on both tricolour packs?
The count is shared, and the stored texts match between the one-pot title at about £19.99 and the three-pot title at about £46.99. Use those reviews as weak evidence for the dearer pack. They include comments about a single 2 litre plant.
What should a distance seller attach that these listings never mention?
A UK plant passport for distance sales of plants for planting in Great Britain. GOV.UK sets that duty for the customer. None of the listings in this set shows a passport on the page. Northern Ireland uses the EU scheme.
Is buddleia legal in a UK garden if I deadhead it?
Growing buddleja in a private garden is not described here as banned under Schedule 9, as that schedule was retrieved. Deadheading still matters if you want fewer seedlings near walls, paving and other structures. Stars on a listing do not answer that question.

Related pages

Buddleia in pots

Buddleia

Best buddleia: top pick, best value and who should skip

Buddleia davidii or Flower Power: flowers and height

How to prune buddleia: late March to mid-April cut

Sources

Public sources from the research digest, last checked on 21 October 2026. Shelf prices and star lines are the amazon.co.uk figures in the display file. The price band is this set, not a market average. No listing was trialled in a garden.

  1. RHS: buddleja growing guide (retrieved 21 October 2026)
  2. RHS: Buddleja davidii (retrieved 21 October 2026)
  3. RHS: Buddleja × weyeriana 'Bicolor' (Flower Power) (retrieved 21 October 2026)
  4. RHS: Buddleja davidii 'White Profusion' (retrieved 21 October 2026)
  5. NNSS: Buddleja davidii (retrieved 21 October 2026)
  6. NNSS risk assessment, October 2020 (retrieved 21 October 2026)
  7. Wildlife and Countryside Act 1981 Schedule 9 (retrieved 21 October 2026)
  8. GOV.UK: plant passports for trade (retrieved 21 October 2026)