I HAVE long suspected that our national obsession isn’t really sport — it’s our backyard lemon and other citrus trees. Switch on any radio gardening talk-back show and the most common problems raised are about someone’s ailing citruses — mainly lemons in cool districts.

The ultimate solution to ageing, congested citrus trees, persistent scale, sooty mould, nutritional deficiencies and destructive swollen galls along branches is a particularly brutal lopping, but it works.

The three most common lemon tree varieties are lisbon (vigorous, thorny tree producing lemons all year round); eureka (also strong-growing, non-stop fruit production, but thornless) and meyer (a small tree with extra-juicy smallish lemons, produced mainly from early winter to mid-summer).

The most vigorous trees can respond to heavy pruning with powerful, new and very healthy growth, the secret of successfully countering most citrus disease and pest problems.

It’s called “skeletonising” and is best to be carried out in late winter or spring, usually every eight to 10 years.

In essence it is a very heavy lopping to get rid of old dead, diseased or pest-infested branches and leaves by completely removing the entire canopy.

The good news is that it doesn’t involve complex, painstaking, nitpicking pruning.

All you need is enough courage to carry out a swift, ruthless operation using a sharp pruning saw or even a chainsaw.

Make sure you wear safety gear, especially strong gloves and full head protection.

Simply slice off the entire top of the suffering old tree, leaving behind nothing more than the bare stumps of main branches, chest-high if you like.

The final result may look completely devastated — just a huge empty space above the stumps and not a single leaf left.

Rake up every bit of debris and if allowed, have a bonfire.

Otherwise chop it into small pieces and pack in strong plastic bags to be tightly sealed and left in the sun for a couple of months.

That kills all pests, including scales, while preventing any gall wasps from escaping and the harmless debris can then be dumped at the local tip.

This massive pruning forces trees to demand extra water and nutrients to keep pace with dozens of shoots that sprout from every branch.

Generously sprinkle pelletised chook manure, mixed trace elements with diluted seaweed extract over the entire root zone and follow with a deep soaking.

Then surround the tree with thick heavy, overlapping layers of newsprint, wetted so they cannot blow away using diluted fish emulsion.

Weigh the lot down with a nourishing, feeding mulch of straw laced with blood and bone and water again.

This newsprint and straw mulch will be dense enough to suppresses weeds while restricting moisture loss through evaporation.

Over the next weeks and months the new growth produced by lopped trees can be phenomenal.

In fact it may be necessary to prune away most of the dozens of powerful shoots growing into the centre of the canopy while thinning those on the outside.

Keep well-watered and fed over summer to keep growth on the move.

In frost-prone districts stop feeding trees in mid-January to avoid vulnerable, tender growth as winter approaches.

Few flowers will appear until the following summer or even later, so don’t expect any fruit during this period of frantic, replacement growth.

It takes about two years after a “skeletonising” prune before lemon trees start to bear fruit again.

When they do, yields of big, juicy lemons can be massive and continuous, this time on pest- and disease-free trees.

And all due to being shocked into new life and vigour by a bit of friendly brutality.