I’ve never heard of a thornless bougainvillea.. sadly! Never got one ’cause I hate getting pricked. What I had as a child whenever we had to get the ball that rolled over to that plant corner is I think enough. 😀
There’s no variety that’s totally thornless I believe. However, there are two varieties known for having very low thorn count namely: “Miss Alice” and “Silhouette”. You might want to take a look at it and perhaps any of them will be pleasing to you.
@wenwen Just got a confirmation from a cousin who’s expert at bougainvillea bonsai making that they are thornless. It seems that the level of hormone responsible for the growth, including thorns, is very minimal due to its intended size. The plant then focuses on growing branches and forgets about the thorns. Now, if that’s something true to other plants with thorns, my cousin couldn’t say.
Thanks for bringing up the topic; rekindles my curiosity!