Every Australian gardener knows about using lilly pillies to make jelly but how many owners of these trees actually make it? Gardeners plant dwarf lilly pillies or grow them as hedges and afterwards discover the foliage can be disfigured by sap sucking pests. It’s not inevitable. Why do so few gardeners and designers think before they plant? 

There are dozens and dozens of allegedly dwarf lilly pilly (Syzygium) cultivars on the market, sold to make compact flowering hedges with beautiful pink flushes of new growth. In reality, most cultivars do not remain dwarf because they are slow growing and, if unpruned, grow pretty large. Rather like the ‘dwarf’ conifers, you get to discover their ultimate size over time.

Rhythmic pruning of a species of lilly pilly is my preferred way to create and maintain a flowering, fruiting hedge. Once they’ve fruited, trim the hedge. Repeat in successive years. Do not expect the crisp lines to remain neat forever, these are living plants. That means they make extension growth in the warm seasons and by next time you next prune they will have a broad, fluffy outline. The pleasure is in the fresh new foliage – it’s beautiful as it changes colour. As a hedge matures, it provides shelter from drying winds and from prying eyes. Nectar rich flowers attract birds and insects. The beautiful fruit can also make aromatic, delicately flavoured jelly.

If you want unblemished, psyllid-free growth, grow Syzygium luehmannii, aka riberry, and its cultivars. If a retailer can’t guarantee a cultivar is of this species, shop elsewhere. Apart from seasonal beauty, this species has beautiful, heart-shaped, lustrous leaves. As a tree, it is drought resistant and suitable for street or avenue planting. Syzygium luehmannii is also known as cherry satinash, creek cherry, lillipilli, cherry alder, scrub cherry and watergum, which is why learning the scientific name saves time, brain space and makes communication accurate. Unless planted by a creek, Syzygium luehmannii rarely exceeds 10m in cultivation and, because this species is less affected by psyllid galls than other lilly pillies, is the best choice of all for hedging.

Established trees tolerate frost to -4C, and as a street tree it survives prolonged drought surprisingly well. Syzygium luehmannii can be grown in large containers, make good lawn specimens, and are useful for screening. Trees tolerate semi-shade but grow best in full sun. Feed once in spring and summer with poultry manure. This adaptable species can be grown in temperate climates, dry temperate and subtropical to tropical climates.

Syzygium anisatum foliage is rich in aromatic oil and, like S. luehmannii, makes a great hedge, but the fruit of this wild spice are insignificant. However, pruning is as much an exercise in aromatherapy as practical horticulture.

I’ve just made coolamon (Syzygium moorei) and bumpy satinash (Syzygium cormiflorum) jelly. Coolamon is an evergreen rainforest species named in honour of Charles Moore, a skilled Scottish gardener and former Director of Sydney Botanic Gardens. Every written reference to this species says the fruit taste bland, but how many authors have actually eaten them at the right time? Nineteen years ago on Gardening Australia I dispelled this myth. Picked at the right time they have a similar texture and taste to crab apples. I used to have these northern hemisphere trees planted as ornamental, fruiting street and park trees. Crab apples still support a niche industry.

The Syzygium moorei I used for the television demonstration is the largest in cultivation and grows by Farm Cove. It is a naturally rare species with large leaves and beautiful pink cauliflorous flowers that smother their boughs in spring. Nectar feeding animals love them; when you hear the lorikeets you know they’re blooming. Every year this grand tree produces fruit by the trailer load. And the lawn mowers wreck them as they run over the botanic turf. It’s sad contemplating rising sea level will snuff this veteran tree out long before old age can claim it, but saltwater encroachment is having a visible effect on trees growing along Farm Cove. There are other cultivated specimens around and their fruit can be salvaged from the lawnmowers of Australia.

Syzygium moorei makes a specimen tree, a large screen or a shelter belt, but it isn’t suitable for a domestic hedge. Not just because it grows too large, but also because its large, glossy leaves are damaged by pruning which makes them look unattractive all year round. This species is unaffected by psyllid and can be grown in a warm temperate, subtropical or tropical climate. Similar species include Syzygium cormiflorum, Syzygium malaccense, Syzygium jambos. Syzygium cormiflorum is palatable, but fruit are spongy and plain and are best used in a blended lilly pilly jelly, unless you’re growing this as a food plant to feed cassowaries. These three have large, glossy leaves making them unsuitable for hedging because the leaves get torn by cutting and look tatty. Grow them as specimen fruit trees. In tropical Queensland, Syzygium cumini is a spectacular native tree but unless you grow it in a cage you’ll have to share the fruit with the birds that spread its seed. So many species relish its fruit.

Lilly pilly jelly

Making lilly pilly jelly is a dying art. It is as varied as the species used to make it, however, expect it to be aromatic and mildly flavoured – perfect for scones.

Method

Fill a pan with fruit. Measure the water it takes to almost cover the fruit. Bring to the boil, simmer for 45 – 60 minutes. Use a colander to strain the water into a container and sit the colander on top to drip. I leave this in place, covered, overnight.

Add the same volume of sugar as was added as water. To every two litres of added water, add the juice of a lemon and one packet of pectin. Bring to the boil and simmer for ten minutes, checking the jelly is ready to set. Sterilise jars and bottle.

To make clear jelly, most recipes say not to break the skin of the fruit. If you’re saving seed for propagation (as I do) get used to making cloudy jelly – it isn’t that cloudy (see picture).  Allowing the jelly to cool and thicken slightly before bottling disperses the cloudiness evenly. Importantly, there’s no flavour difference.

From 750g of Syzygium fruit I sowed forty seven seed and produced 1.5 litres of coolamon jelly; a rarely made product from a naturally rare species.

Planting

To plant, thoroughly loosen clay soils, working in plenty of compost. Water requirements increase where plants are grown in deep sand, such as Perth. Syzygium are unsuitable for sodic (saline) soils. Quite a few species tolerate frost once established. However, for the first three years after planting it’s important to water saplings during drought and to protect them from hard frost.

Let’s keep planting the right lilly pillies for trouble-free hedges, a diversity of Syzygium species to enhance our environment, and to keep our culinary traditions alive.

If you’re interested in unusual food, crops and plants, why not join Jerry Coleby-Williams on his

Jerry Coleby-Williams
Director, Seed Savers’ Network Inc.
17th February 2020