The genus Ceanothus includes about fifty species of shrubs originating in northern and central America; the genus is quite varied, and the shrubs are very different in size depending on the species: from 35-45 cm in height of Ceanothus tyrsiflorus, a small ground cover, up to 465 meters in height of Ceanothus arboreus, a true and own tree. Some species are evergreen, others with deciduous leaves; in general, deciduous species are more resistant to cold.
In general, however, all the ceanoti have oval leaves, dark green, shiny on the upper side, and crossed by deep veins; in spring or summer they produce countless fragrant little flowers, gathered in huge racemes, elongated or with a ball. The peculiar characteristic of the ceanoto is certainly in the color of the flowers, a deep and intense blue sky.
The flowering of the ceanoto has made it a very popular garden shrub also in Europe, and over the years different varieties and cultivars have been produced, with white, blue and even deep blue flowers, more or less fragrant, sometimes odorless.
In the nursery in Italy it is very easy to find the ground cover varieties, of small dimensions, with spring flowering; more rarely, often only in the most supplied nurseries, there are also varieties with summer bloom, of average size, from 50 to 120 cm in height.
Grow a ceanoto
These shrubs come from a wide range of areas, and therefore have various cultivation needs; in reality, however, in the nursery we can easily find only species and varieties with similar needs, suitable for our garden.
They are placed in a good soil, moderately rich, well worked and enriched with manure or slow release granular fertilizer; they fear water stagnation, so it is absolutely imperative to lighten the soil with sand or other material that makes it well permeable. They can withstand drought, although it is advisable to water them regularly, when the soil is well dry.
We choose for our ceanoto a fairly bright and sunny place, possibly avoiding to place it in an area of the garden or terrace that is excessively windy, or exposed to the north: we prefer areas that are very hot and fairly sheltered from the weather.
Species found in Italy generally do not fear the cold excessively, in any case in autumn we mulch the soil around the roots with straw or dry leaves, so that the most intense frosts do not reach the root system in depth; in the event that the frost should ruin the outermost branches, at the end of winter we prune the plant, removing only the ruined branches; generally the development of the ceanoto is well compact and dense, and the growth rather slow, therefore it does not need pruning.
A plant adapted to the fire
Ceanotes are very common in America, where they are called California Lillas; in some wooded areas there are many, and the production of seeds, given the large inflorescences, is massive.
The seeds produced by the ceanoto are generally fertile, but nature has prevented them from germinating all together, given that such a large number of seeds would produce such a quantity of seedlings, which would quickly die for lack of space.
The seeds of ceanoto are covered with an impenetrable peel, and it is said they can remain fertile for hundreds of years; these seeds can germinate only after remaining on the ground for years, at the mercy of the weather, or after the plant from which they were produced has been destroyed by fire; after a fire the seeds sprout quickly, bringing back the vegetation where the disaster has destroyed it.
Ceanoto - Ceanothus: Sowing
Therefore, if we want to sow the small seeds produced by our ceanoto, we remember that it is not possible to make them germinate simply by placing them on the ground and watering them, as often happens with many other seeds.
Before sowing them we will have to place them in warm water for 12-24 hours, then put them in the refrigerator for 1-2 months, at about 3-4 ° C, and only then will we be able to sow them, considering that many of them will not germinate.
Many other plants have developed this method to preserve seeds; in nature the seeds simply fall close to the plant that produced the fruit, if they all sprouted, nobody would have enough space to develop, not even the made plant.
So these seeds germinate only when space has been created around them, as in the case of a fire; or only after having been digested and evacuated by a small animal, which possibly also transported them far enough from where the mother plant had deposited them.
It looks like an exotic behavior, but so do the seeds of many species of tall trees, like many conifers or maples.