Multi stem California lilac (Ceanothus 'Trewithen Blue)

[Iffyh]

Hi there

I have recently planted a multi stemmed California Lilac. I want it to grow into a tree with the majority of leaves and blossoms in an umbrella shape at the top - is it as simple as keeping the 3 or 4 larger stems at the bottom and trimming all the other stems lower down off every time they sprout?

 

[Iffyh]

Picture below

 

[Meadowlark]

Welcome @lffyh

The umbrella shaped ones I've seen usually have one main stem that is selected to become the trunk of the umbrella shaped tree...not sure about 3-4 stems, if I understood correctly. The strongest one becomes the main trunk.

I've seen it recommended that the best time to prune is after the blooming period to avoid cutting off next season’s flowers and avoid cutting back more than 1/3 of any branch.

 

[cpp gardener]

Do you want a multi-trunk tree or more of a single-trunk standard? It really is as simple as choosing how many trunks and removing the ones you don’t want. You will get some resprouting for awhile, but it will eventually stop. If you want a more spreading multi-trunk, you can stake each trunk separately at different angles.