Ceanothus species

Seed - best sown as soon as it is ripe in a cold frame. Stored seed should be pre-soaked for 12 hours in warm water and then given 1 - 3 months stratification at 1°c^[3][4]. Germination usually takes place in 1 - 2 months at 20°c^[3]. One report says that the seed is best given boiling water treatment, or heated in 4 times its volume of sand at 90 - 120°c for 4 - 5 minutes and then soaked in warm water for 12 hours before sowing it^[5]. The seed exhibits considerable longevity, when stored for 15 years in an air-tight dry container at 1 - 5°c it has shown little deterioration in viability^[5]. The seed is ejected from its capsule with some force when fully ripe, timing the collection of seed can be difficult because unless collected just prior to dehiscence the seed is difficult to extract and rarely germinates satisfactorily^[5]. Prick out the seedlings into individual pots as soon as they are large enough to handle. Grow them on in the greenhouse for at least their first winter and plant them out into their permanent positions in late spring or early summer. This is a garden hybrid and it will not breed true from seed.

Cuttings of half-ripe wood, taken at a node^[4], July/August in a frame^[6].

Cuttings of mature wood of the current year's growth, 7 - 12 cm with a heel, October in a cold frame^[7]. The roots are quite brittle and it is best to pot up the callused cuttings in spring, just before the roots break^[7]. Good percentage.

Prefers a warm sunny position but tolerates light shade^[6][4]. Tolerates some lime, but will not succeed on shallow chalk^[4]. Some of the cultivars included here are tolerant of clay soils^[8].

Plants dislike root disturbance, they should be planted out into their permanent positions whilst still small^[9]. Dislikes heavy pruning, it is best not to cut out any wood thicker than a pencil^[9]. Hybridizes freely with other members of this genus^[4].

Some members of this genus have a symbiotic relationship with certain soil micro-organisms, these form nodules on the roots of the plants and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby^[4][10].