You have several options here Kat:

Semi-ripe cuttings should be taken in mid-autumn, placed in a cold frame...or in mid-spring in a propagator, misting frequently (this is quicker).

You can sow seed in early to mid-spring in an outdoor seedbed.

or

By division in early to mid-spring...replanting the portions immediately in their permanent positions.

I know this doesn't answer your question of taking tip cuttings now....try these options if your tip cuttings don't take now.

Thankyou Amblealice as I have a nice christmas box in garden I wanted to try to propagate for now have got tip sitting in water to see if they will self root.

Good luck !....let us know if it takes....

Thankyou will experiment.:)