Don’s Expert Answers: Poor growing Lilly Pillies

Question From:
Adam Hall in Northgate, Brisbane Queensland

Nature of problem:
Poor growing Lilly Pillies

Type of Plant (if known):
Syzygium australe aka “Hinterland Gold” Lilly Pillies

Symptoms of Plant Illness (please try NOT to diagnose your problems yourself):
No new growth (leaves) on base of plant. Instead of “bushy” screens, resembling trees with “clear” trunk and limited growth on top.

Soil Type (e.g. sandy, clay or loam) OR Potting Mix Type:
Moderately reactive clay and silt (clayey sand to 30cm depth; silty sand to 60cm depth, silty clay at further depths).

How often do you water the plant:
At least twice per week.

How many hours of sunlight does the plant get each day:
The tops would get about eight hours of sunlight each day.

How long since you planted it:
Three years.

Have you fertilised? If so, with what and when:
Yes. Seasol seaweed fertiliser every six months.

Is the plant indoors or outdoors:
Outdoors.

Is the plant in a pot or in the ground:
Ground.

What other treatments have you given the plant:
Yates Confidor tablets to help combat pimple psyllids (which has been successful).

Upload photo if available:

Other Comments:
We have approximately 30 “Hinterland Gold” Lilly Pillies which were planted three years ago for privacy around the three sides of our backyard.

As we were seeking privacy, we did not prune or trim the Lilly Pillies during their initial growth (which we now realise may have been a mistake). Although the Lilly Pillies have now reached the desired height (ranging from 2m along the sides to 4m along the back), they’re extremely sparse. The “trunks” are almost bare and what leaves there are at the “top” of the trees aren’t particularly bushy or full.

The sparseness of the greenery has adversely impacted the privacy benefits of the trees. We had also hoped to create a “green” walled oasis, but now the surrounding fence is clearly visible as there is minimal greenery on the “trunks” of the trees.

We would prefer a bushier, hedge-like garden, even if we have to sacrifice some of the height (which is still needed for privacy). We’re not sure how to best approach this (e.g. to significantly trim the tops of the trees (i.e. 0.5 to 1.0m removed) which would, for presumably at least a few months, leave us with almost completely bare trunks or to try something else).

Any assistance and advice would be greatly appreciated.

Answer:
Hi Adam, Always take Dale’s idea from ‘The Castle’: dig a hole. Use a small trowel to dig a number of holes that are 15cm deep about 30cm from the base of sickly plants. I expect that the soil will be very dry. Lillypillies are water lovers as they come from rainforest areas. Apply Saturaid soil wetting agent and water the plants with a sprinkler for 90 minutes twice a week for several weeks. Then install a poly pipe irrigation with at least one sprinkler-head per plant. Good luck. don