Can't find silicon tube clips for grafting
I live in the UK, not the US, and am unable to find silicon tube clips for grafting heirloom tomato seedlings scions onto disease resistant rootstock. I was wondering if I could improvise and just use normal silicon tubing by just cutting off a 2cm length? If so, what inner diameter tubing should I use (when people give the diameter I never know if they mean the inner or outer diameter!)?
I really see no reason why it wouldn't work and can't see what is so special about purpose made silicon grafting clips but a second opinion would be reassuring. Thanks.