Alan's guide to shrub sizes

Shrubs can be bought in a range of different pot sizes to suit your budget and how immediate an effect you want. Small potted shrubs will take several years to reach the stature of larger, more expensive shrubs, so you may need to employ bedding plants or perennials temporarily, to fill gaps between smaller shrubs until they reach a larger size.

Discover the most frequent shrub sizes on sale, plus their benefits and drawbacks, in Alan Titchmarsh's guide to shrub sizes.

Small pots or liners (9cm)

Rooted cuttings or seedlings that have been grown on for a short while.

• Pro: cheap, easier to get established and a higher success rate
• Pro: useful size to plant in mixed container displays, where they can grow to a larger size before planting out
• Con: deciduous shrubs rarely available
• Con: need potting up to grow on for a few months before planting out, unless you plant them as a hedge or dwarf edging

These plants are approximately one to two years old and cost around £1.50-£4.

Standard pots (1-2 litres)

The most popular standard size sold in garden centres. Nurseries will have potted up liners into the next-sized pot and pinched out the top growth to produce a bushy, branching plant.

• Pro: wide choice of species and varieties
• Pro: garden-ready, need least after-care
• Pro: root and establish quickly
• Con: not all will bloom in their first year
• Con: may have become pot-bound while waiting to be sold at garden centres

These plants are around two to three years old and usually cost £7-£15.

Large pots (3-5 litres)

Bigger plants, either as a result of being fast growing, or because they have been potted up and grown on for a year or two more than the standard size (above).

• Pro: usually wide choice available, both deciduous and evergreen varieties
• Pro: garden-ready, need little aftercare
• Pro: often sold in flower or will bloom in their first season after planting
• Con: may have become pot-bound while waiting to be sold at garden centres

Usually around four to six years old, costing £10-£25.

Semi-mature plants (5+ litres)

The largest size in our guide to shrub sizes. Semi-mature plants are often large evergreens, trimmed shrubs, topiary or trained fruit bushes.

• Pro: instant effect; look as if they’ve been growing in the garden for several years
• Pro: can be stood on the patio to use as tub plants for a season before planting
• Pro: good soil preparation and regular watering needed for first summer, and can suffer badly in hot dry weather
• Con: may have become rootbound while waiting to be bought at garden centre

Semi-mature plants are usually five to eight years old, and cost from £20-£100+.

Containerised roses

Roses are available all year as containerised plants – that is lifted from the nursery field in winter and potted up for sale.

• Pro: can be planted all year
• Con: less choice available as containerised plants from garden centres than as bare-root plants sent out direct from rose nurseries in the dormant season (usually November to February)

Containerised roses sold are usually around two years old and cost £10-£15 potted.

Looking to buy perennials or trees? Take a look at Alan's perennial size guide and tree size guide, to find out what to expect for the price you pay.