Californian lilac
Evergreen ceanothus
Evergreen ceanothus
Choose a sheltered site from the start — this group is notably more prone to winter losses in cold, exposed gardens than the hardier deciduous hybrids.
Care
Sheltered from cold winds — a warm wall is ideal.
Once established — drought-tolerant.
Free-draining soil of low to moderate fertility; dislikes heavy, waterlogged clay.
Trim lightly after flowering only; never cut back into old bare wood, which won't reshoot on this group. If the plant needs hard, renovating pruning every spring instead, it's very likely the separate `deciduous_hybrid` group below, not this one.
Don't feed. This is a Californian plant of poor dry hillsides; on fertile soil or with fertiliser it grows fast, soft and short-lived, and is far more likely to be killed outright by a cold wet winter.
Semi-ripe cuttings in late summer, in very gritty compost kept only just moist. Worth taking as routine — evergreen ceanothus are short-lived and resent hard pruning, so a replacement in the wings is the sensible plan.
Month by month
Months change with the climate: in southern Italy tomatoes go out two months earlier than in England.
- MarchLight feed as growth resumes. how ›
- MayTrim lightly after the main spring flowering flush — never into old bare wood. how ›
- NovemberIn exposed gardens, provide some winter wind shelter for young plants. how ›
Months based on climate: UK. Your choice stays on this device.
- MarchLight feed as growth resumes. how ›
- MayTrim lightly after the main spring flowering flush — never into old bare wood. how ›
Months based on climate: Northern Italy. Your choice stays on this device.
Common problems
How to spot it. To the foliage in a hard winter, especially on young or exposed plants.
What to do. Site against a warm, sheltered wall.
How to spot it. Can affect stressed or old plants.
What to do. Remove and dispose of affected material, avoid replanting Ceanothus in the same spot.
Deciduous ceanothus
Deciduous ceanothus
Confirm which type is planted before the first spring prune — if in doubt, evergreen types keep their leaves through winter and must only be trimmed lightly after flowering, while this deciduous group loses its leaves and is cut back hard every spring. Applying the wrong regime is the biggest risk with this genus.
Care
Full sun; benefits from shelter but is markedly hardier than the evergreen types, so it tolerates more open sites.
Once established — reasonably drought-tolerant.
Free-draining soil of low to moderate fertility; dislikes heavy, waterlogged clay.
Cut back hard every spring, to within a couple of buds of the previous year's framework — flowers form on the current season's growth, so this hard prune produces more and better flowering, not less. This is the opposite regime to evergreen Ceanothus, which must never be cut into old wood.
A light spring feed at most, on poor soil. These flower on the current year's growth after a hard spring prune, so the prune does more for flowering than any fertiliser will.
Semi-ripe cuttings in late summer, or softwood cuttings earlier from the new growth. Both root more willingly than the evergreen kinds.
Month by month
Months change with the climate: in southern Italy tomatoes go out two months earlier than in England.
- MarchCut back hard to a low framework as growth resumes — this group flowers on new wood, so a hard spring prune is correct here, unlike evergreen types. how ›
- AprilLight feed as strong new growth gets underway after the hard prune. how ›
- AugustMain late-summer flowering, later than the evergreen types.
Months based on climate: UK. Your choice stays on this device.
- MarchCut back hard to a low framework as growth resumes — this group flowers on new wood, so a hard spring prune is correct here, unlike evergreen types. how ›
- AprilLight feed as strong new growth gets underway after the hard prune. how ›
- AugustMain late-summer flowering, later than the evergreen types.
Months based on climate: Northern Italy. Your choice stays on this device.
- FebruaryCut back hard to a low framework as growth resumes — this group flowers on new wood, so a hard spring prune is correct here, unlike evergreen types. how ›
- MarchLight feed as strong new growth gets underway after the hard prune. how ›
- AugustMain late-summer flowering, later than the evergreen types.
Months based on climate: Central Italy. Your choice stays on this device.
- FebruaryCut back hard to a low framework as growth resumes — this group flowers on new wood, so a hard spring prune is correct here, unlike evergreen types. how ›
- MarchLight feed as strong new growth gets underway after the hard prune. how ›
- AugustMain late-summer flowering, later than the evergreen types.
Months based on climate: Southern Italy and islands. Your choice stays on this device.
Common problems
How to spot it. Can affect stressed or old plants.
What to do. Remove and dispose of affected material, avoid replanting Ceanothus in the same spot.
How to spot it. Less of a risk than for evergreen types, given the greater hardiness of this group, but young plants still benefit from shelter in their first winters.
What to do. Site out of the harshest winds while establishing.
Popular varieties
Questions
Californian lilac: is it hardy?
H4: Hardy through an average UK winter. It survives down to −10 °C.
Can it grow in a pot?
Evergreen ceanothus: For a few years while young, though it ultimately prefers open ground against a sheltered wall. Deciduous ceanothus: Suits a large pot well, since the hard annual pruning keeps it naturally compact.
Californian lilac: when do you prune it?
Evergreen ceanothus: Trim lightly after flowering only; never cut back into old bare wood, which won't reshoot on this group. In the calendar for UK, pruning falls in May. Deciduous ceanothus: Cut back hard every spring, to within a couple of buds of the previous year's framework — flowers form on the current season's growth, so this hard prune produces more and better flowering, not less. In the calendar for UK, pruning falls in March.
Californian lilac: when does it flower?
Evergreen ceanothus: In the climate of UK it flowers in May–June. Deciduous ceanothus: In the climate of UK it flowers in July–September.
When do you feed it?
Evergreen ceanothus: Don't feed. This is a Californian plant of poor dry hillsides; on fertile soil or with fertiliser it grows fast, soft and short-lived, and is far more likely to be killed outright by a cold wet winter. Deciduous ceanothus: A light spring feed at most, on poor soil. These flower on the current year's growth after a hard spring prune, so the prune does more for flowering than any fertiliser will. Feeding months, UK: April.