And the ideal way is to use drip irrigation.
Feb 26, Pruning a Waratah. cosmicgardener February 26, My neighbour has a huge Waratah tree - about 10 metres high which has wonderful blooms - but - they are right at the top of the tree where they cabn't be appreciated fully except by the black parrots that seems to like the tree.
He asked me if he could prune it to a 'manageable height' - i.e. Apr 12, I have a waratah that got hammered on New Year's Day as well. It's looked better but will come good between now and flowering time in October. The answer to your question is yes, they can be pruned, have done so several times and it comes back bushier.
They are frost hardy to degrees C.
Cultivated Waratahs require heavy pruning once established. About a third to half of the plant should be removed immediately after flowering to reinvigorate the plant. New shoots should flower the following year.
Waratahs flower in a six week period in spring in the Sydney region, but later in cooler areas. The main pollinator of Waratahs are birds. Prune flower stems by half to three-quarters, to increase the number of flowers for the next year. Once your plant gets to 10 years, it’s time to be ruthless. Cut back the canes completely to the lignotuber (swollen base) after flowering (it will flower again the following.
Aug 30, Prune them at about waist level just above a healthy bud. That way you get a beautiful display of flowers at eye level the following year.