Ceanothus arboreus (Californian Lilac)

Probably the fastest growing plant on the nursery – it could reach 20 ft in 5 years BUT, and this is quite a big ‘but’, giving it a haircut from time to time (immediately after its early summer flowering) makes it a much more handsome plant. It keeps the foliage denser and you can control the shape. As long as it has plenty of light and space, it grows almost anywhere, on a wide range of soils. The blue flowers are prolific and fragrant and highly attractive to butterflies. They’re so keen to flower that you’ll often get them to flower twice – May and then October. As I write, it’s late November and we have masses flowering on the nursery right now. Like many Californian plants – fast growing but not long lived. About 15 years on heavy soil, up to 40 years on well drained soil. As with all plants known for their drought resistance, they need masses of water when first planted but once established, never again. There’s a fine collection of old Ceanothuses at Cambridge Botanic Garden. They like the low rainfall of East Anglia and the well drained soil around Cambridge.

Propagated by us from cuttings. The original plant was a rather fine hedge (it makes a good hedge) that Peter the propagator found in Kingston-upon-Thames in 1989.

N.B. When clipping several plants with the same tool, have a bucket containing a 5% bleach solution and swish your blades around for 30 seconds between plants to sterilise them. This will help avoid the chance of cross contamination of disease.

As with all woody plants, plant high, exposing as much of the taper at the base of the trunk as possible. Allowing soil to accumulate round the base of a tree can be fatal. Keep very well watered when first planted.

Hardiness level Amber

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IF IT HAS A AMBER TRAFFIC LIGHT

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Hardy in the Home Counties if sensibly sited (avoiding severe frost pockets, for example). Many Amber Labelled Plants are from cuttings from well-established plants that have survived many harsh winters in the South-East.

This is only meant as a guide. Please remember we're always on hand to give advice about plants and their frost hardiness.

Please remember that these coloured labels are only a rough guide.

General Point about Plant Hardiness: The commonly held belief that it's better to 'plant small' is perfectly true with herbaceous plants, but not necessarily true with woody plants. They need some 'wood' on them to survive severe cold - so plants of marginal hardiness in very cold areas should really be planted LARGER, rather than smaller, wherever possible.